Sunday, May 18, 2008

The Block Universe

I was just about to throw away Petkov's paper "Is There an Alternative to the Block Universe View" when I realized I totally forgot to let you know my conclusions about it.

In my earlier post Every Now and Then I explained why I think the most plausible explanation for our perception of the now being different from the past and the future is due to the ability of our brains to store memory. I thus believe in the 'block universe' in which there is nothing special about the now, and the past and the future exists in the same way as the present moment.

Nevertheless, I want to point out this isn't more than a believe of mine that I personally find plausible. Especially, I do not think it follows from Special Relativity, as some comments indicated - and as also Petkov argues in his paper. Here, I want to explain why I don't think his argument holds. I will pick around on Petkov's paper not because I dislike it so much, but because it is actually a useful summary that also contains a brief historical introduction on the previous work on the issue, most notably the Rietdijk-Putnam argument [1,2].

Please note that the following does not take into account quantum mechanics, with which everything becomes much more complicated.



Preliminaries

The following should be familiar to everybody who has opened a textbook on Special Relativity (SR), so excuse me for being somewhat brief with the basics. In SR one can construct the surface of simultaneity of an inertial observer, Bob, in a straight-forward way. One puts two lights in equal distances into the restframe of the observer (meaning their relative velocities vanishes). If Bob measures signals from both lights to arrive at his worldline at the same time, he says they were emitted simultaneously. Doing this for lights of all possible distances creates a surface, called the 'surface of simultaneity' on which all events lie that happen at the same time according to Bob. One can repeat this for all instances on the world-line of the observer, which gives a slicing of simultaneity. For the observer in rest, these are just parallels to the x-axis in Minkowski-space.

If one considers a second observer (Alice) moving with a relative velocity to Bob, she can do the same construction. It turns out however, her notion of simultaneity is a different one, and her slices of equal time are not identical to those of Bob. The reason for this is that the speed of light is constant in SR and the same for all observers. If Alice's and Bob's world lines cross at one point (e.g. the origin), the events they consider simultaneous with this meeting are on two different lines that form an X.

This is illustrated very nicely in this figure from the Wiki-commons. Here, event B is simultaneous with A in the green reference frame, but it occurred before in the blue frame, and will occur later in the red frame.



The argument then goes as follows: if everything exists that Bob calls simultaneous but there is nothing special about Bob, then everything that Alice calls simultaneous exists the same way. You can repeat this for all observers that cross either of these already existing surfaces anywhere and you'll fill up the whole space. Thus, everything in the four-dimensional plane exists, because everything lies on somebodies surface of simultaneity.

There was a criticism of this argument by Stein [3] which I didn't read so I can only tell you what Petkov says about it. Apparently Stein's criticism is that the notion of present but distant events does not make sense, since one can not say anything about the 'now' that is not also 'here', so one should talk only about the 'here-now'. To reformulate this into Bee-speech, I'd say the argument is you can't have information about the 'existence' of anything that is not (yet) causally connected to you, like everything on your space-like slice is. Thus, concluding it 'exists' just because you measure it later is not possible. (This is probably a very fanciful interpretation of mine about a paper I didn't read, apologies.)


Claims

Petkov wants to show that

1) The block universe view, in which the universe is regarded as a timelessly existing four-dimensional world, is the only one that is consistent with Special Relativity.

2) Special Relativity alone can resolve the debate on whether the world is three-dimensional or four-dimensional.

I will in the following argue that 1) is wrong and 2) is correct. For being able to conclude anything at all, I will start with explaining what I am talking about. There is a possibility I am not using the terms as your philosopher next door does, but at least you know what I am talking about
  • a) The block universe is a 3+1 dimensional space time with Lorentzian signature in which there is no present moment that is special in some regard.

  • b) Presentism means there is a notion of 'now' and it is only the 'now' that exists. This can be further sub-divided in to categories

    • b1) Presentism in which time is a parameter.

    • b2) Presentism in which time is not a parameter.


For maximal carefulness I want to point out that another assumption which also goes into the argument is

A) Time is either a parameter or a dimension and there is no other possibility.

If that wasn't the case one could never make a claim like 'is the only option consistent with' as done in 1). To call upon the Principle of Finite Imagination, one should however keep in mind that this is an unproved assumption and an alternative option can't be outruled. I will understand SR as the relativity of all observations in all inertial frames. Sorry for nitpicking, but I want to throw out all merely philosophical baggage that isn't observable - you'll see later why.


In Media Res

For the reader who has taken a class in SR the rest of the argument is now actually trivial.

Let us start with claim 2): We know that time can't be a universal parameter because we have experimental prove the passage of time depends on the state of motion and path of an object. Thus, presentism b2) is falsified, which means with A) time is a dimension. It follows 2) is correct.

Now to claim 1): The first observation is that one should be skeptical about this claim because it involves the notion of 'existence' which doesn't appear in SR altogether. So how can one possibly say whether some sort of 'existence' is compatible with SR?

I'll give you an analogy. I could ask you whether my invisible friend is compatible with complex analysis. At the very best, you could say the question doesn't make sense, or to make it sound somewhat more sophisticated, it is ill-defined. Unless I tell you something about my invisible friend, there is nothing incompatible because in complex analysis there are no invisible friends. If I now told you my invisible friend is an entire function that is bounded but not constant, you could go and prove this is incompatible with complex analysis (via Liouville's theorem).

So how come Petkov as Rietdijk and Putnam can and do say anything about claim 1)? Well, the reason is that they don't actually explain anything about 'existence'. Instead, they say the 'now' does 'exist', thereby exporting 'existence' into a concept that can be defined in SR: the 'now'. Since I do not want to define 'existence' either, I too want to export it into the 'now'. This then however doesn't allow us solve the problem addressed in 1), for there is no reason why the 'existence' should be bound to the 'now' in the way one can define it in SR.

Let me make that more precise. The 'now' in SR can be constructed using surfaces of simultaneity in the usual way as mentioned in the prelimiaries. This is a definition of now. It doesn't say anything about existence. If you however use this definition of now, and say what is 'now' according to this definition 'exists', then you suddenly have a definition for existence. Cool, eh?

However, this is a definition and not a conclusion, as you can't say anything about whether something exists on your surface of simultaneity elsewhere, you can only say something exists if it's not only 'now' but also 'here'.

That, so I gather was also the argument by Stein mentioned above.

So, the flaw in the argument is that you can very well have a notion of a 'now' that 'exists' that is not in disagreement with any measurements confirming SR because there is no reason to define 'presently existing' with the surfaces of simultaneity in SR. In fact, everything that can be said about 'existence' in SR is a completely empty statement.

To see this, put an 'existence - slicing' with a time parameter τ on Minkowski-space [4] and say for each τ it is only the respective slice that 'exists', or is 'now' - according to this definition of 'now'. This can't be in conflict with experiment, for you never measure 'existence' anywhere than where you are. What you measure are signals from elsewhere and/or elsewhen. Yet on which 'now' slice these signals sat with you at emission is completely irrelevant. All that matters is that the propagation takes place according to the laws of SR because that's what we have measured. This is not a block-universe because it has a notion of a present moment, but is not in disagreement with any predictions by SR.

Thus, 1) is wrong.

Below an illustration to this.



Anyway

There is however two more things to be said here:

One is that this option is compatible with all our measurements, but it does of course break observer-independence as a matter of principle for singling out some slicing means singling out preferred restframes.

The other one is that this option is compatible with Special Relativity and all measurements because it doesn't have any observables whatsoever and is not falsifiable. To make this an interesting scenario, you'd have to tie some observables to the 'existence-slicing' (if you think GR that could e.g. be the restframe of the CMB).


[1] Rietdijk, C.W. A Rigorous Proof of Determinism Derived from the Special Theory of Relativity, Philosophy of Science, 33 (1966) pp. 341-344
[2] Putnam, H. (1967) Time and Physical Geometry, Journal of Philosophy, 64, (1967) pp. 240-247
[3] Stein, H. On Einstein-Minkowski Space-Time, Journal of Philosophy, 65, (1968) pp. 5-23
[4] You would want to make sure it fulfils some nice-ness features of slicing like that the slices don't cross, are space-like, and cover all of space etc.



TAGS: , , , , ,

195 comments:

Andrew Thomas said...

Very interesting, but quite mind-boggling and I don't quite get it yet. Maybe you can help me!!

You seem to suggest at the start that if you are causally connected to something (i.e., you can see it) then it "exists": "like everything on your space-like slice is". Is that right? You seem to say that. But that means if you have two observers (who can see different events in different orders) then you can have different models of existence. So how can you have a single "existence slicing" for the whole universe, as you suggest? Surely it's all observer-dependent, multiple slicings? Have I misunderstood you?

Andrew Thomas said...

I've read it a couple more times (!!) and I think I'm starting to get it! You're saying there's some kind of ABSOLUTE planes of "existence" (i.e., nothing to do with observer dependence), which are defined for all times, t. And as our observers move around, they get a "picture" of those existence planes. You can never measure "existence" anywhere than where you are, you can just see how things where in those past "existence slices". And it's not a block universe because only one "existence slice" exists at any one time. Am I getting any closer?!!

Bee said...

Hi Andrew,

No, I do not say that what you see exists. In the preliminaries I summarize the Rietdijk-Putnam argument for completeness. Later I explain why the conclusion can't be made.

You can have a single 'existence-slicing' because there is no notion of 'existence' other than the one you define (as long as it doesn't lead to complete nonsense like you'd have for example if the slices intersect with themselves).

Does this help?

Best,

B.

Bee said...

Hi Andrew,

Sorry, our comments intersected. Yes, your second comment is exactly what I meant to express! Best,

B.

Andrew Thomas said...

It's very clever. You should publish!

Bee said...

:-) Glad you like it. Yes, I should publish - I should publish that damned draft on my desk I've rewritten now roughly a billion times.

Andrew Thomas said...

How would it cope with the twin paradox, though? Two observers at the same here/now position, one shoots of near the speed of light and comes back again, and you find there's 70 years difference on their clocks. That would appear to indicate that they've each experienced a different number of "time existence planes" passing by, even though they started at the same here/now position and ended-up at the same here/now position? I dunno.

Bee said...

The twin paradox rules out that time is a universal parameter, but that isn't the case here. The (eigen)time that passes on a world-line depends on the path as usual, just as in SR. The eigentime does not just measure the number of slices passed, it's an integration over the curve.

Andrew Thomas said...

Yeah, I can accept that. Things slow down for the astronaut, but there's still just one existence plane.

Anonymous said...

A Fresnel zone analogy, in the sense of all the events that can illuminate Bob at his same time. And the slices being different means the "Fresnel zones" are different too.

I like.

Plato said...

Many-worlds interpretationThe simplest way to see that the many-worlds metatheory is a local theory is to note that it requires that the wavefunction obey some relativistic wave equation, the exact form of which is currently unknown, but which is presumed to be locally Lorentz invariant at all times and everywhere. This is equivalent to imposing the requirement that locality is enforced at all times and everywhere. Therefore many-worlds is a local theory. Another way of seeing this is examine how macrostates evolve. Macrostates descriptions of objects evolve in a local fashion. Worlds split as the macrostate description divides inside the light cone of the triggering event. Thus the splitting is a local process, transmitted causally at light or sub-light speeds.
—Michael Clive Price[3]


Thought of Antony Valentini breaking the cryptology sequence, seemed, relevant here?

Giotis said...

Hi Bee

I need another example. Could you tell me how this works with the Andromeda paradox which is another version of the Rietdijk-Putnam argument?

Regards

Bee said...

Hi Giotis,

The Andromeda argument is as far as I know it the same as the Rietdijk-Putnam argument, it just sounds more illustrative. The fact of whether an event happens (will happen, did happen) doesn't say anything about whether it 'exists' in some version of 'now'. As I mentioned above, this is a purely classical argument. There is no uncertainty about any evolution whatsoever. If you have sufficient initial conditions on one slice, you can predict everything on every other slice. Yet that doesn't tell you whether the slice 'exists' or whether you have some other 'existence-slicing'. Does that help?

Best,

B.

Giotis said...

Ok, thanks Bee. τ is the proper time?

Bee said...

In the figure above? No, sorry about that, it's just some time-parameter labeling the slices. The t was already gone for the Minkowski coordinates and τ was the first thing that came into my mind. Maybe not such a great choice.

stefan said...

Thanks for the write-up and the illustration! I guess eventually I start to understand what you want to say ;-)

There are sometimes discussions about the conventionality of "simultaneousness" in special relativity, and that the standard Einstein convention may not be the only consistent way to define simultaneity (I've always found this quite confusing and never have thought too much about it)..

Now I wonder, is there a relation to the "existence-slicing"? I mean, if I understand that correctly, "existence" is defined as "being simultaneous" in the "standard" meaning of the word, so, could a new convention for existence via the explicit slicing imply a different convention for simultaneity?

Cheers, Stefan

Bee said...

Ooohm, I dunno coz I've never come across such a discussion, so can't say anything without a reference.

Phil Warnell said...

Hi Bee,

Very interesting since it approaches the question from a different perspective. So time remains personal as is demanded by SR and existence can only be defined real/relevant from its own frame of reference. Therefore, all nows are only unique in terms of ones reference to personal existence. From this perspective then it leaves ones preexisting past set, the now being formed and the future what, as it relates to ones personal reference of existence? The question is irrelevant however if I have not understood what you are saying.

Best,

Phil

Giotis said...

Hi Bee,

I have trouble understanding this "existing slicing" and the difference with the simultaneity plane.
Wherever you put the origins of the beams, they will still always be in some observer's simultaneity plane. You can't avoid that. So why we need the existing slicing?

Or am i missing something?

Regards

Bee said...

Hi Giotis,

No, you're not missing anything. You don't need that slicing, that's exactly the point. It doesn't change anything about SR. You can put it there and say it's only one of the slices that exists in each moment and the other ones don't, or you can not put it there, it doesn't matter. What I am saying is just that SR doesn't force you to believe in any specific notion of 'existence' (the block universe vs presentism) because it doesn't say anything about existence whatsoever.

Best,

B.

Bee said...

Hi Phil,

I am afraid I didn't understand your question. In essence, the reason for this to work is that we can never decide which notion of 'existence' is 'correct' in the sense of which slicing it is because all we ever experience is existent now AND here. So that leaves a lot of ambiguity to define existence-slicings as long as the laws of SR are fulfilled. Best,

B.

Giotis said...

Hi Bee,

Sorry for being persistent. But if this is the case and you connect simultaneity with existence, then the fact that the origins of the beams have to be in the simultaneity plane of an observer (I mean it is mandatory to be) then SR forces you to accept the block universe.

Regards

Phil Warnell said...

Hi Bee,

“So that leaves a lot of ambiguity to define existence-slicings as long as the laws of SR are fulfilled.”

Yes I think I understand this. Another way to state it is that time is not a parameter yet rather existence is and one that is arbitrary. So then ones past is a place of the there-then, ones present a place of the here -now, with ones future being a place of the ( )-( ). Could this be wherever-when? It sounds like this arbitrary parameter forms a built in uncertainty or preclusion to knowledge as I like to look at it.

Best,

Phil

Bee said...

Hi Giotis,

No, because the origins of the beams don't have to exist on my slice of existence for me to be able to detect the signals later. They could have existed 'earlier' or 'later' according to my existence-slicing, that doesn't matter.

Hi Phil,

I'd not have said existence is a parameter, but the existence-slicing is a parametrization of hypersurfaces. I guess that's what you mean, just to clarify that I don't mean a parameter as being one of a curve. Best,

B.

Bee said...

Hi Giotos again,

I don't connect simultanaety in SR with existence, that's the point I'm criticising. Best,

B.

Bee said...

Err, I meant Giotis. Nice name btw, what does it mean?

Giotis said...

Hello Bee,

Ok sorry, now i get it, i think. You are saying that you don't have to connect existence with simultaneity within SR, because even if we had this hypothetical existence slicing (not the simultaneity plane) to define existence, then we wouldn't know the difference with the laws of SR.

Am i right?


Giotis is greek. It doesn't mean anything, it's just a short version of my name.


Regards

Phil Warnell said...

Hi Bee,

“I'd not have said existence is a parameter, but the existence-slicing is a parametrization of hypersurfaces. I guess that's what you mean,”

Yes the slicing in relation to existence is what I meant. When you combine this with your connection of the mind with the now, as it relates to the flow of time, it sounds almost like Descartes, except instead of “I think therefore I am” it would be “As I think to exist therefore I am”.

Best,

Phil

Bee said...

Hi Giotis,

Yes, you got it :-) 'Existence' remains a merely philosophical term that SR doesn't say anything about.

Never been to Greece, always wanted to!

Best,

B.

CarlBrannen said...

That the special theory of relativity is believed true is an indication that all the usual laws of physics do not depend on the reference frame. From this follows all the logical arguments, but it doesn't quite have to be that way.

An alternative is to assume that there is a preferred reference frame, but that there is no law of physics that can detect it. Our calculations don't depend on the reference frame, preferred or not, so this assumption gives the same consequences as the usual special theory of relativity.

The advantage of an undetectable preferred reference frame is that "now" can be defined with it. But that also means that you can't make a physics experiment that detects "now."

I'm basically following the arguments of David Bohm on this. A certain infamous string theorist (who I have great respect for but generates ill will by calling everyone an idiot and consequently can't be mentioned by name on a lot of blogs) has a post on the subject, or see, especially Section 6 of On some early objections to Bohm’s theory by Myrvold.

Plato said...

3-d: no hidden dimensions 1/R2 in F = G(m1 x m2)(1/R2)
4-d: one “ “ 1/R3 replaces 1/R2
5-d: two “ “ 1/R4 “
6-d: three “ “ 1/R5 “


The complexity of the determination arises in the interpretation of a way in which to measure dimensions greater then 3 or 4? Such "real examples" then become thought experiments about simultaneity, and the way to interject this into that dimensions greater then 3 or 4? Hmmmmmm.....I don't kown


Exploratory data analysis provides a way for human observers to interact with such high- dimensional data sets, studying collections of views obtained by projecting the data down into two- or three-dimensional spaces. It may be that various configurations of data resemble configurations already observed by studying images of model structures, not just lines and planes but also more complicated curves and surfaces. Our experience with the phenomena of geometry of curves and surfaces in three- and four-dimensional space provides the tools for interpreting data configurations which arise from real-world observations.

Just thinking out loud.

Lumo said...

These are scientificially meaningful words. Show me an operational meaning of these words. In other words, how the world would look like or "feel" if the present were perceived in the same way as the past?

Perception (or consciousness) is *defined* (and cannot be defined otherwise than) some feelings or processes at a particular moment.

When we use the past tense, "perceived", these processes occur in the past, when we use the future tense, "will perceive", they occur in the future, and the present tense, "am perceiving", refers to the present.

There is nothing else physical that can be said about these trivial matters. It is just a creation of philosophical bubbles where no legitimate problem to study exists.

Giotis said...

Hi Bee,

"Never been to Greece, always wanted to!"

Well, you should come. Greek islands are amazing during summer. I recommend Santorini.

Regards

Phil Warnell said...

Hi Carl,

“That the special theory of relativity is believed true is an indication that all the usual laws of physics do not depend on the reference frame. From this follows all the logical arguments, but it doesn't quite have to be that way.”

I have to thank you for that paper you pointed to as I wasn’t aware of it before. Also I never did give you a proper hello,as for the first time I saw you here and recalled you from Trevor’s Bell/Bohm board. I enjoyed the synopsis of the arguments this paper presents, in particular the point raised where with the acceptance of a preferred frame (aether if you will) being at the expense of symmetry is considered . More recently Prof. Harvey Brown has written a book entitled “Physical Relativity” which supports the dynamical perspective with no appeal to a privileged frame of reference. I must advise however that when it comes to Quantum Theory he appears to be an Everett man:-)

Best,

Phil

P.S. I never did find that Levitron to see if I could get the darn thing to work :-)

Bee said...

Well, I see Lubos has written a lengthy commentary on presentism vs eternalism. Since leaving comments at his place is usually a big mistake, here's some words to the visitors who read his hiccup:

Notwithstanding the fun Lubos is trying to make of me, he doesn't do much but repeating somewhat more inelegantly what I also wrote. Namely that how you define the word 'exist' doesn't change anything about our theories. You can assume some criteria for 'existence' that you find reasonable but as long as those aren't observable this doesn't have consequences whatsoever. In short, unless you come up with a well-defined theory-of-existence, theoretical physics won't be of much help.

As to his remark "I find it kind of mind-boggling (it not mind-blogging) that the very same people who like to say that statements in science must be falsifiable - and who even enjoy to lead their impressionable readers to the completely wrong conclusion that even very accurate, quantitative, and a priori incredibly strong scientific statements are not falsifiable - are usually the very same people who are absolutely excited about meaningless philosophical babbling about questions that can be given no operational meaning."

I can only say that what I blog about it my decision, and besides this, if you read at least the last sentence, you'll realize that I've criticised the question for being non-falsifiable. Please note, if you believe in the Rietdijk-Putnam argument presentism is falsifiable. I am surprised actually Lubos doesn't defend Rietdijk-Putnam and/or Petkov.

As to free will, I don't think we have one. But that's a different topic.

Phil Warnell said...

“There is nothing else physical that can be said about these trivial matters. It is just a creation of philosophical bubbles where no legitimate problem to study exists.”

It is interesting to note what J.S. Bell’s perspective was in regards to such considerations when he said the following:

“The approach of Einstein differs from that of Lorentz in two major ways. There is a difference of philosophy , and a difference of style.

The difference of philosophy is this. Since it is experimentally impossible to say which of the two uniformly moving system is really at rest, Einstein declares the notions ‘really resting’ and ‘really moving’ as meaningless. For him only the relative motion of two or more uniformly moving objects is real . Lorentz, on the other hand, preferred the view that there is indeed a state of rest, defined by the ‘aether’, even though the laws of physics conspire to prevent us from identifying it experimentally. The facts of physics do not oblige us to accept one philosophy rather then the other. And we need not accept Lorentz’s philosophy to accept a Lorentzian pedagory. Its special merit is to drive home the lesson that the laws of physics in any one reference frame account for all physical phenomena, including the observations of moving observers. And it is often simpler to work in a single frame rather than hurry after each moving object in turn.

The difference of style is that instead of inferring the experience of moving observers from known and conjectural laws of physics, Einstein starts from the hypothesis that the laws will look the same for all observers in uniform motion. This permits a very concise and elegant formulation of the theory, as so often happens when one big assumption can be made to cover several less big ones. There is no intention here to make any reservation whatsoever about the power and precision of Einstein’s approach. But in my opinion there is something to be said for taking students along the road made by Fitzgerald, Lamour, Lorentz and Poincare. The longer road sometimes gives more familiarity with the country.”

-J.S. Bell “How to teach special relativity”-Progress in Scientific Culture, Vol. 1, No. 2, summer 1976

I suspect then that John Bell also should be accused of drawing attention to the relevance of “philosophical bubbles”. In this regard all I can say is that I have grown to have a fondness for them.

Best,

Phil

Phil Warnell said...

Hi Bee,

“As to free will, I don't think we have one.”

Would that be in the context of a ‘private will’ or a ‘collective will’? :-)

Best,

Phil

Bee said...

Neither.

Phil Warnell said...

Hi Bee,

“Neither.”

I then look forward to your expansion on such thoughts if you “decide” to share them:-)

Best,

Phil

Andrew Thomas said...

If we live in a block universe then the future is just as "set in stone" as the past, so we don't really have free will in the usual sense. It's just like having a girlfiend or a wife - you just kiss goodbye to free will and accept your fate with a smile

Bee said...

That's because the classical theory is deterministic, not because it's a block universe. It is quite interesting that despite the fact that Laplace pointed this out very clearly:

"An intellect which at a certain moment would know all forces that set nature in motion, and all positions of all items of which nature is composed, if this intellect were also vast enough to submit these data to analysis, it would embrace in a single formula the movements of the greatest bodies of the universe and those of the tiniest atom; for such an intellect nothing would be uncertain and the future just like the past would be present before its eyes."

There weren't many objections to this removal of free will.

Andrew Thomas said...

Yes, if the future is deterministic (clockwork universe) then free will is an illusion because everything just ticks forward according to a plan. But it's also true that in an indeterminisitc block universe the future is just as "real" as the present and the past - they are all on the same footing. Whether it is deterministic or indeterministic is irrelevant: the future is "out there" in the 4th dimension exactly the same as the past is "out there". We can't change the past - and our impression that we can change the future would be just an illusion. They all have the same degree of "reality" or "existence", future and present and past, all the same. Time passing is an illusion. Free will is an illusion. That's the block universe for you.

Bee said...

Hi Andrew,

Yes, I just meant to say, the underlying reason in the theory why there is no free will is not that you assume a block-universe but that the evolution equations are deterministic.

If evolution isn't deterministic you could potentially have many past-states that lead to the same present-state. How do we know then we can't change the past if evolution was non-deterministic? Anybody ever went and looked?
Best,

B.

Phil Warnell said...

Hi Bee,

“It is quite interesting that despite the fact that Laplace pointed this out very clearly:………..
There weren't many objections to this removal of free will.”

Good point and yet with the considerations within quantum theory even a deterministic one can leave room to wonder; for when David Albert was discussing the Bohmian perspective in his book 'Quantum Mechanics and Experience' he said the following:

“On Bohm’s theory, there is, right now (that is : before those upcoming measurements get carried out) an objective physical matter of fact about what the future act of h’s is going to be: and (moreover) h knows with certainty, what that act is going to be; and (moreover) no other observer in the world (no matter how adept they may be at measuring or calculating) can possibly know (right now) what that act is going to be.

And so h, under these sorts of circumstances (even though the complete physical theory of the world here is a deterministic one), has what you might call an inviolably private will.”

This does then deny LaPlace’s “enity of intellect” the knowledge required. The question then that still remains is that even if this will is "inviolably private" does this also infer it to be free?

Best,

Phil

Bee said...

Hi Phil,

Yes, but Laplace didn't know anything about quantum mechanics. That's what I find funny, there has been a whole century in which the status of physics said there is no such thing as free will, yet this insight doesn't seem to have reached very many people - or maybe it did, but it didn't bother them. Either way, I find this absense of objection remarkable. Sure, the present state of things is to put free will into quantum mechanics.

Best,

B.

Phil Warnell said...

Hi Bee,

“ Either way, I find this absense of objection remarkable. Sure, the present state of things is to put free will into quantum mechanics.”

If one considers that the western inspired philosophy of many at time more or less boils down to fate, I am not all that shocked. Getting back to deterministic as opposed to non deterministic for me has always come down to what is uncertainty. That is it preclusion as of a consequence of the restriction of ability or is compounded by a restriction within nature’s laws to know. When ability is the only consideration “free will” must be certainly a mirage. However, if it is compounded with nature’s censor in knowing, there still may be some reason to wonder.

Best,

Phil

Plato said...

I guess we can dispense with the modelling of geometrics, and the breadth and depth of such generalizations, as we now know "computers are an illusion too?":)

Nothing behind them, the words empty, as one tries to express themself, using means that are just a further extension of the "hallucinatory nature of people in time?"

So perfection, or truth, sought after, are not to be found anywhere, other then, what you convince yourself fit for the truth, only to find,we are just fabricating more illusions.

"So what is real then?"

As to freewill, you think you are not able to change your circumstance? How sad:) You "set the tone." Doesn't matter what the debate on with non-deterministic physics saids.

Maybe, string theorist's align themselves with Hugh Everett? Oui! Non?

Rae Ann said...

Re: Free Will

Maybe this is a bad question or my not really understanding the intricacies of these things, but how can you eliminate free considering quantum uncertainty? It seems that there is a certain probability (but not absolute certainty) that things will turn out a particular way, but as one moves from the smallness of quantum to the bigness of SR where exactly does the uncertainty (and therefore free will possibility) disappear?

Sorry if this is a stupid question/comment. Just imagine that I'm a grandma. ;-)

Bee said...

Hi Rae Ann,

No it's not a bad question, it's just that I didn't actually want to discuss it (people seem to like the topic, but not my opinion on it). I don't want to eliminate free will (like, actively), I just doubt we have one to begin with. If one considers free will to be a matter of consciousness, then things get very complicated. But yes, at least one can say the standard interpretation of quantum mechanics does not require you to accept its absence as a purely deterministic theory would. That there is some uncertainty doesn't prove you have one either. Best,

B.

Andrew Thomas said...
This comment has been removed by the author.
Cynthia said...

Time, IMO, is what makes the 'block universe' less block-like. Equally so, space is what makes the 'blockless universe' more block-like.

It's also my opinion that the 'here-now' is just a slice of spacetime. And each and every one of these slices has either more space than time or more time than space. But there's no such thing as a slice having space without time or time without space -- unless there's such a thing as either a 'block universe' or a 'blockless' one.

Serenus Zeitblom said...

Hey, Bee, I no longer have the patience to wade through LM's increasingly lengthy, repetitive, and boring disquisitions. But skimming through it, I noticed one statement that was undoubtedly true:

"Even though I have written a lot of words by now,"

CapitalistImperialistPig said...

Bee,

This is a quibble, but the way you have defined the surface of simultaneity as the surface from which "lights of all possible distances" arrive simultaneously is actually the past light cone, though I guess we all knew what you meant.

The claim that "Time is either a parameter or a dimension and there is no other possibility" is hard for me to accept or even understand. When you foliate spacetime as you did above, you certainly make time a parameter, I'm not sure what you mean by "dimension," unless you mean the trivially true statement in SR that different observers could foliate it differently.

Quite different seeming descriptions can be equally compatible with reality though. As Mark Srednicki points out in is QFT book, in non relativistic QM we treat spatial coordinates as observables, but time as a parameter, but in QFT it's usual to make both parameters. As he also points out, the alternative idea of promoting time to an operator also works, even though it is more complicated, and both give the same physics.

Block time vs presentism may be a matter of point of view. If you take the god like point of view of standing outside spacetime and observing it, it looks pretty blockish. From the standpoint of an individual immersed in spacetime and swept along by it, not so much. Free will versus determinism might be similar.

Andrew Thomas said...

(Why doesn't this system let you edit a comment you have posted?)

Rae Ann, I don't see how indeterminism is any better than determinsm for giving you free will. If your actions are determined by a throw of a dice (essentially, random quantum indeterminism) then how does that give you free will? You're just following what the dice says.

With that in mind, it would appear that any definition of "free will" which depends in some way on fundamental physical processes is always going to be doomed. Because it can never be truly "free" then - it's going to be dependent on either deterministic clockwork or indeterministic dice!

I think the only way you could possibly have free will in the sense you mean would be to have consciousness which is not influenced by any fundamental physical processes at all, either deterministic or indeterministic. But I really don't see how you can have any brain process with that definition.

I think it's just your definition of "free will" that is screwed (if "free will" is to have any hope at all). I think it's possible to make another, equally valid definition of "free will". Personally, I **define** my free will in the following way: free will is the ability to make decisions. I think it's unarguably the case that we all have that ability - I make decisions all the time. I have free will in the same way I have "emotions" - both absolutely real. So by my definition, I have free will. But I think your definition was screwed. It's nothing to do determinism/indeterminism, or fundamental processes - that doesn't come into it. It's a high-level human thought process, and we all definitely have it.

So I think a discussion about free will probably does not belong in a science blog. That's not to say it's anything mystical - I'm just saying it probably would be better suited in a psychology or medical physiology blog. After all, if we treat free will as a high-level thought process then it's now clear to see who has it: I have it, but a coma patient doesn't have it. It's a medical condition.

To back me up in my definition and defense of free will, here's a couple of scanned pages from Michael Lockwood's book "The Labyrinth of Time": "It does not follow that there is no sense, consistent with Einstein's view, in which we genuinely affect the course of events. We are surely still entitled to think of ourselves as painting the future".

The Labyrinth of Time

Cynthia said...

Spacetime within the context of the uncertainty principle posits that the more you know about space, the less you know about time, and vice versa. But because simultaneity in spacetime (whether viewed as a tiny and simple slice or as a huge and complex 'block universe') allows you to know, at any given moment in spacetime, everything about space and time, simultaneity in spacetime is in clear violation of the uncertainty principle.

Bee said...

the uncertainty principle posits that the more you know about space, the less you know about time

? The way I know the uncertainty principle it relates conjugated variables, unless you are talking about a non-commutative space-time.

Bee said...

Andrew: (Why doesn't this system let you edit a comment you have posted?)

To teach commenters to think before they hit publish ;-)

Especially the anonymous ones (who can't even delete their comments).

More seriously, if it was possible for everybody to edit comments lateron, a sensible discussion would become completely impossible.

Giotis said...

Hi Bee

I was thinking again the concept of the "existence slicing" and i have some considerations about it, for which i want your opinion if possible.

For example consider the case where the emission of the two beams (in your figure) at their origin is controlled by two scientists. They are both equipped with the usual synchronized clocks of SR and their world lines are straight lines (they are both at rest). You can also put for simplicity the world line of one of them to coincide with the t axis. A third scientist has arranged to perform a number of SR measurements for which to be performed is required the two beams to be received simultaneously.

The two scientists on the other hand have agreed to fire their beams when they measure (measure not see) each other's clock to indicate a specific (the same) time. We assume that somehow this is technically possible and that the three scientists don't know anything about their existence planes, they only know that SR is the theory that describe their world.

If the two scientists "exist" in a plane other than the simultaneity plane ( i.e. the locus of events with the same SR clock reading), then they will not be able to measure the correct time (at each other's clock) simultaneously and consequently the third scientist won't be able to perform his measurements because the other two will not fire the beams simultaneously.

So if the existence plane does not match the simultaneity plane we won't be able even to perform these SR measurements/experiments. The fact that such experiments can be performed in a SR environment indicates that the simultaneity plane should match the "existence plane".

The argument is that the simultaneity plane should be the only possible "existence plane" in SR because it is through the simultaneity plane that one can "understand" i.e. measure the world around him.


Regards

Bee said...

Hi Giotis,

If the two scientists "exist" in a plane other than the simultaneity plane ( i.e. the locus of events with the same SR clock reading), then they will not be able to measure the correct time (at each other's clock) simultaneously and consequently the third scientist won't be able to perform his measurements because the other two will not fire the beams simultaneously.

The two scientists will both 'exist' in some existence-plane, in which their clocks will show the correct time to send the signal. Whether that is the same plane for both of them, or how else it does look like doesn't matter as long as signals can propagate appropriately from the sender to the receiver. In the picture above, the senders would 'exist' at a later value of the parameter τ that is the parameter of the slicing, and at this slicing their clocks (eigentime) would show the time to send the signal .

Best,

B.

Giotis said...

Thank you Bee

Just to make clear that when i say that they are both equipped with the usual synchronized clocks of SR,
i don't mean the clocks that measure their proper time i.e. they don't carry them. I mean the clocks in their vicinity and that one measures the time indication of the clock in the vicinity of the other.

So you are saying that the two scientists will measure the same time indication for these clocks even if they do not "exist" in the same simultaneity plane. Correct?


Regards

Bee said...

Hi Giotis,

You said the observers are in rest (presumably with the x-axis?) so their eigentime is just the t-axis? If that's not what you meant, I don't know what time you're talking about.

What I am saying is that the one scientist will 'exist' in some simultanaety plane in which his clocks shows the same as that of the other observer on potentially some other 'existence' plane (that might have existed earlier or later in terms of τ). It is completely irrelevant whether or not they sit on the same τ plane when their clocks show the same t-time.

Best,

B.

Anonymous said...

Bee:

I think you (along with many of those who have commented) are conflating two different senses of the verb, “to exist.” You seem to be asking, which is more real, the phenomenon or the nuomenon. In the first case, we have physical existence, in the sense that an object can be said to exist if it exhibits properties that we can measure. In the second case, we have formal existence, in the sense that the limit of an infinite series can be said to exist if we can prove that the series converges.

Existence which is amenable to measurement is fundamentally different from existence which depends only on proof, and it makes no sense to ask which is more real. To see what I mean by this, grant me for the sake of argument that the earth exists, and that it orbits the sun. Then, which is more real, the earth or the orbit?

The answer of course, is that they both exist, but in a different way, and both are equally real, each in its own way. The earth belongs to the realm of phenomena, and the orbit belongs to the realm of nuomena.

Similarly, the present moment has phenomenal existence, while the past and the future have nuomenal existence. To lose track of that distinction leads us into logical fallacies of the sort committed by proponents of the “many worlds” interpretation or the claim that the observer “creates reality.”

plato said...

Your confusing the "interpetations of intution" that exist.

plato said...

To busy for source reference...ummm..intuition,sorry

Phenomenon" in Phenomenology is that which is known by consciousness and in it. Phenomenologists regarded intuition as a "pure", direct, and primitive way of reducing clutter in reality. It is immediate and the basis of a higher level perception. A philosophical system built on intuition would, perforce, be non speculative. Hence, Phenomenology's emphasis on the study of consciousness (and intuition) rather than on the study of (deceiving) reality. It is through "Wesensschau" (the intuition of essences) that one reaches the invariant nature of things (by applying free variation techniques).

Anonymous said...

Plato:

Sorry, but I have no patience for intuitionism. It renders mathematics futile and empty. The only purpose it serves is to provide science with a seductive rationalization for committing suicide.

Giotis said...

Hi Bee,

Yes this is correct. The proper time will be just the t-axis. But the key point here is that the two scientists have agreed not to fire the beams according to their proper time but according to the time they measure on the clock in the vicinity of the other.
So A measures the time indication on the clock in the vicinity of B (where B stands, that is the clock of the SR rigid frame) and correspondingly B measures the time indication on the clock in the vicinity of A (where A stands, again that is the clock of the SR rigid frame).

If they measure just their proper time then yes, you are right. But anyway i an not sure whether the configuration i describe has a real meaning and now that i examine it again i don't like it, so I'm dropping the whole issue.


Regards and thanks for your time

plato said...

In a 1998 interview, Pribram addressed the understanding of cognitive potential, stating that, "(I)f you get into your potential mode, then new things can happen[citation needed]. But usually free will is conceived of in terms of how many constraints are operating, and we have in statistics a notion of degrees of freedom. I think our will essentially is constrained, more or less. We have so many degrees of freedom, and the more degrees of freedom we have, the more we feel free, and we have freedom of choice."

Andrew Thomas said...

That's very interesting. I suppose a prisoner (or someone in China, for that matter) has fewer degrees of freedom. Does that mean they have less free will? I would guess it does.

Bee said...

Hi Giotis,

time but according to the time they measure on the clock in the vicinity of the other.

You said, you are talking about the time they 'measure', not see on the other's clock. They are both in rest, so if this time on their clocks is not t then I don't know what you are talking about, could you clarify?

Either way, I don't understand what you are trying to say anyway. They either agreed to emit both signals on the SR simultanaety plane (however they did agree on this), then the signals will arrive simultaneous. Or they didn't, then they won't arrive simultaneous. For neither situation it is of any relevance how the 'existence-slicing' looks like.

Best,

B.

Bee said...

Hi Anonymous,

I think you (along with many of those who have commented) are conflating two different senses of the verb, “to exist.” You seem to be asking, which is more real, the phenomenon or the nuomenon.

Though this is an interesting comment of yours, I explicitly explained in my post I'm not attaching any meaning to the word 'exist'. You can attach to it whatever meaning you wish - it doesn't matter, SR doesn't tell you anything about it. That's all I was saying.

Similarly, the present moment has phenomenal existence, while the past and the future have nuomenal existence. To lose track of that distinction leads us into logical fallacies of the sort committed by proponents of the “many worlds” interpretation or the claim that the observer “creates reality.”

I never claimed that the observer 'creates reality', so who or what are you referring to? Your statement that "the present moment has phenomenal existence, while the past and the future have nuomenal existence" is not only unproved but unprovable. It is merely an expression of your perception of 'existence' and entirely meaningless unless you explain how you can measure a difference between both kinds of 'existence' of the past and/or future.

Hi Plato,

Your confusing the "interpetations of intution" that exist.

You are confusing interpretation with observation. I don't care how you interpret 'existence'. What I'm saying is that however you interpret it, it isn't in conflict with any observation we have - it can't be unless you write down a sober and testable theory. In the absence of this I happily leave the discussion of 'existence' over to the domain of the philosophers.

Best,

B.

Plato said...

That's very interesting. I suppose a prisoner (or someone in China, for that matter) has fewer degrees of freedom. Does that mean they have less free will? I would guess it does.

Knowing you have the degrees of freedom and knowing that you are constraint by that very government does not mean it's people have less freewill, just that, censorship is prevalent. Not on how the computers are used.

Are they different from you? Have you forgotten Plato's cave?:)Freeing people, from being chained?

Giotis said...

Hi Bee,

I mean that if they exist in another plane other than the simultaneity plane they will not be able to match their readings. Let's say that they have agreed to fire their beams at 12. When A measures the time on the clock in the vicinity of B to be 12 fires his beam but B will not measure 12 on the clock in the vicinity of A and thus he will not fire his beam. He will measure a different value because they don't exist in the same simultaneity plane. The beams will never be fired simultaneously and the third scientist won't be able to perform his experiment.

Since this experiment can always be performed in a SR environment we deduce that the two scientists have to "exist" in the same simultaneity plane. At least that was the original idea when i was thinking about it now i am not so sure:-)

Regards

Plato said...

Bee:You are confusing interpretation with observation.

On the contrary, Bee.

I may spread words like "self evident" "Aristotelean Arc" and make one think of Franklin's revision to Jefferson's wording, alongside of, "the declaration of independence," but it is more then that.

This is a quest for the "inductive and deductive statement" about the "decomposable definition" that will result in the derivative of new mathematical interpretations.

How are new concepts formed in maths, if this element was never thought of? Do we have to be reminded of these elements in terms of the non-euclidean geometries, to know that at one time, they were speculative, but sought by inquisitive minds, to wonder about the fifth postulate.

Bee said...

Hi Giotis,

I think you have a very confused notion of the time A and B measure. You say

"When A measures the time on the clock in the vicinity of B to be 12 fires his beam but B will not measure 12 on the clock in the vicinity of A and thus he will not fire his beam."

A can not 'measure' anything he is not causally connected to, so you can't mean that literally. I thought you were trying to say they've synchronized their clocks some time in the past and now have a notion of 'time' the other's clock shows, which I thought you meant to be the time t. I ask you again, if this is not the time you are talking about, neither is is their eigentime, then what are you talking about? I really don't know what you are saying.

He will measure a different value because they don't exist in the same simultaneity plane.

Are you trying to say the time they agreed on sending the signals out is the time τ? Then why would you expect the signals to arrive simultaneously? Let me repeat once again what I said above: it does not matter at which τ A or B 'exist' to send their signals out, neither does it matter whether it is the same τ. All that matters is there is some τ that crosses the SR simultanaeity plane where they do send it out.

Best,

B.

Bee said...

Hi Plato,

The point of this post is to show that the observations we have that confirm SR are not in disagreement with the idea that 'existence' - whatever that is - is a quantity that can be assigned to only three-dimensional submanifolds if sliced appropriately, because relating 'existence' to the 'now' in SR ('now' as defined by the surfaces of simultaneity) is an additional assumption, and one for which there is no justification.

If you want to find a maths concept for 'existence', you're welcome. I have no objections to that.

Best,

B.

Rae Ann said...

Andrew, the question is 'at what point does the "random quantum indeterminism" become the determinism you impose on the Chinese prisoner'?

Bee, sorry for opening this can of 'unscientific' worms. Obviously, I am closer to being a grandma than a physicist and if my comments are too distracting just say so and I'll go cook or sew or something. ;-)

Bee said...

No problem. As long as you don't expect me to reply anything sensible, have fun.

bellamy said...

...if it was possible for everybody to edit comments lateron, a sensible discussion would become completely impossible.

Given the topic, one thinks such is the case, regardless.


Yes, you got it :-) 'Existence' remains a merely philosophical term that SR doesn't say anything about.

And following from my response above: it seems the existence of such ideas as addressed in this topic are based in a fundamental emotional conflict.


And to Cynthia: indeterminacy refers to the ability of any subset (for example, humans) of the cosmos to model it. The cosmos itself, is deterministic.

Giotis said...

Hi Bee,

Of course i don't mean it literally, they are spacelike separated. But this is merely a technicality. In SR the observer can always assign theoretically a time to an event by "looking" at the clock placed on the location of that event i.e. assign a time t on an event at position x,y,z. This is how the inertial frame is constructed. The clock i am talking about belongs to the inertial frame and is located where the scientist stands. It's not his wrist watch. The wrist watch measures his proper time and indeed it measures the same time with the clock located at his position because he is at rest. But lets forget about it for a second. Lets say B forgot to wear it:-)

When i say A measures the clock in the vicinity of B (or simply observes B if you want) i mean exactly that action i.e. the action to assign a time "t" to the scientist standing at position x,y,z. You can say that the very physical existence of the scientist is the event i guess.

How A does that? By drawing simultaneity planes parallel to his X axis. Through simultaneity planes A "measures" or understands the world around him. Since B does not live in the simultaneity plane of A, how is it possible for A to assign the correct time to B (in the way i described this action above)or even assign a time at all? I can only assume that he couldn't. I deduced that B does not live in the simultaneity plane of A because in your post you say:

"there is no reason to define 'presently existing' with the surfaces of simultaneity in SR."

In a nutshell what i am trying to do is connect existence with simultaneity although i understand your argument too.

Unfortunately i can't express it any better. Still it doesn't make sense?

Regards

Anonymous said...

Bee:

Yes, of course you are right. SR has nothing to say about existence. SR simply pre-supposes the existence of phenomena like clocks, meter-sticks and so on. However, it also pre-supposes the existence of reference frames and world lines, which are nuomena. And it is the failure to distinguish between the two that leads people like Petkov to the conclusion that SR demands a block universe.

I did not accuse you of claiming that the observer creates reality; I was merely giving additional examples of the sorts of mistakes that follow from failing to distinguish phenomena and nuomena.

You do, however, state that you “believe in the ‘block universe’ in which there is nothing special about the now, and the past and the future exists in the same way as the present moment.” But you think this is a matter of belief, and not a matter of fact. And you call my claim, that the past and future exist in a way that is different from the present, unproved and unprovable. So I will have to show that it is provable by proving it.

To that end, let me return to the example of the earth orbiting the sun. I can measure the position of the planet at successive times, but I cannot measure the orbit – I must calculate it from my measurements. Thus I can observe the phenomenon, but I must infer the nuomenon. Nonetheless, if you take similar measurements, you will infer the same orbit (within experimental error). Thus the orbit is real – it exists – but it does not exist in the same way as the planet. Now, the orbit is nothing other than the world line of the centroid of the planet; it is the locus of the past, present and future positions of the planet. But the planet itself is only available for measurement in the present moment. Thus the past and future of the planet (summarized for simplicity by the world line of its centroid) have nuomenal existence, while its present moment also has phenomenal existence. QED.

You also express your view that “the most plausible explanation for our perception of the now being different from the past and the future is due to the ability of our brains to store memory.”

I think this puts the cart before the horse. Our brains obey the laws of physics. Not the other way around. Our memories are not of the future for the same reason that mountains do not un-erode: the arrow of time is objectively real. Everywhere and at all times it points in the same direction. This does not depend on our presence to notice it. It was that way long before we were here to notice, and it will still be that way long after we are gone.

Andrew Thomas said...

Rae Ann, I don't think anyone is quite sure how we get the classical macroscopic world from the random quantum world (this hasn't got anything to do with the block universe, by the way). One simple way I look at it is, imagine each random quantum measurement is represented by one game on a roulette wheel in a casino. You can't predict the outcome of each spin of the wheel. But in the long run, the casino knows it will win because it knows the odds are on its side (quantum mechanics gives you the probability of an outcome, and you never see a poor casino). So you get determinism (the casino always wins) from randomness - as long as you take a large number of measurements (many roulette games, or a large number of atoms in a body).

Bee said...

Hi Giotis,

No, sorry, it doesn't make sense. If both observers A and B are in rest, and in rest with the x axis, then their inertial frames are the same, and their time is just the Minkowski time, which is also their eigentime, which is exactly the case that I depicted above, and that I've explained repeatedly. Anyway, I think your problem is not in the time-definition or inertial frames but in the following:

Since B does not live in the simultaneity plane of A, how is it possible for A to assign the correct time to B (in the way i described this action above)or even assign a time at all? I can only assume that he couldn't. I deduced that B does not live in the simultaneity plane of A because in your post you say:

"there is no reason to define 'presently existing' with the surfaces of simultaneity in SR."


I never said 'B does not live' in the simultanaety plane. A can very well assign a time to B on that plane, even if B does not 'exist' at the same τ as A. B sending a signal is just an event, and A assigning a time to it is putting a coordinate system on the manifold we call our space-time. There is no reason to define presently existent with the surfaces of simultaneity in SR, because - as I said above - B does not have to 'exist' at the same τ together with A in order to send out the signal that is later measured simultaneously with that of A.

Best,

B.

Bee said...

Hi Anonymous,

And it is the failure to distinguish between the two that leads people like Petkov to the conclusion that SR demands a block universe.

Well, as I've written in my post, I think the reason for this faulty conclusion is not the failure to distinguish between different kinds of existence, but the assumption that SR provides some special definition of 'existence' that lies on the simultanaety planes.

Your 'proof' that 'the past and future exist in a way that is different from the present' is not meaningful. You try to explain there is a difference between a planet's orbit and the planet. Then you make a jump and conclude the past and the future is different from the present. The only thing you can conclude from this is if you do a measurement, then your ability to measure the present is different from your ability to measure the past or the future.

You state

can measure the position of the planet at successive times, but I cannot measure the orbit – I must calculate it from my measurements. Thus I can observe the phenomenon, but I must infer the nuomenon.

You use the fact that you can measure something but not the other to explain what you mean with 'existence', and later you want to conclude from it what exists - it's a circular argument. You have simply defined existence in a way that you like it.

You also express your view that “the most plausible explanation for our perception of the now being different from the past and the future is due to the ability of our brains to store memory.”

I think this puts the cart before the horse. Our brains obey the laws of physics. Not the other way around. Our memories are not of the future for the same reason that mountains do not un-erode: the arrow of time is objectively real. Everywhere and at all times it points in the same direction. This does not depend on our presence to notice it. It was that way long before we were here to notice, and it will still be that way long after we are gone.


Yes, our brains store memory of the past but not of the future because there is an arrow of time, and our brains obey the laws of physics. How does that let you conclude the present moment is somehow different from the past and the future - except for your subjective perception that this is the case? What I am saying is one shouldn't forget that our brains are complicated devices and that paying attention to subjective perceptions can be very misleading. For more details, please read this earlier post.

Best,

B.

Anonymous said...

Hey Bee

i was thinking about this too and thought id misinterpret a whole bunch of terms and concepts i know little about to make sense of it...hahaha

http://pollywannacracka.blogspot.com/
2007_06_01_archive.html

basically, the guts of it is "for every choice made in this universe there is an equal and opposite one being made in another"...

...free will then becomes the freedom to choose any given option by a YOU that exists only in this universe knowing another YOU made the opposite in another

Anonymous said...

Bee:

I’m not sure what’s at the root of our disconnect regarding existence. Do you disagree that the planet and the orbit both exist? If not, then do you disagree that they exist in different ways?

Regarding the specialness of the present moment, you write “I believe the reason for this is that a system as complex as our brain is able to store information gathered on the worldline in its memory.” Bee, it doesn’t take consciousness – or even complexity – to endow a system with memory; all it takes is dissipation.

You also write “If you just draw a trajectory of a particle moving on a world line... you can't find anything like a ‘now’ because it doesn't have anything like a memory.” But this is only true after you have finished drawing it. While you are drawing, ‘now’ is at the point where the line is lengthening! The line itself is the memory of where the pencil-point has been. That’s why there is no ‘now’ on the line after the pencil finished drawing.

And of course, human consciousness is not necessary for any of it. One can just as easily imagine a rock, dislodged from a mountaintop by weathering, sliding down the slope and leaving a track as it goes.

In either case, the present moment it where the action is – where a process is happening. The past is what did happen, and the future is what could happen. But that distinction only makes sense if there is a boundary in between where something does happen.

Bee said...

Hi Anonymous,

I’m not sure what’s at the root of our disconnect regarding existence. Do you disagree that the planet and the orbit both exist? If not, then do you disagree that they exist in different ways?

The disconnect is: I am trying to tell you I can not agree or disagree on this question unless you explain what you mean with 'existence', and you don't notice that you are making additional assumptions which allow you to draw conclusions that however depend on these assumptions.

Regarding the specialness of the present moment, you write “I believe the reason for this is that a system as complex as our brain is able to store information gathered on the worldline in its memory.” Bee, it doesn’t take consciousness – or even complexity – to endow a system with memory; all it takes is dissipation.

Indeed. I never said consciousness is necessary to have a memory. It however seems to be sufficient. I don't know how you want to ask something with memory but without consciousness whether it perceives a present moment that is special in some sense.

In either case, the present moment it where the action is – where a process is happening. The past is what did happen, and the future is what could happen. But that distinction only makes sense if there is a boundary in between where something does happen.

That's a further collection of undefined words like 'process' and 'to happen' and 'boundary'.

Best,

B.

Anonymous said...

Bee:

If I say that “to exist” means “to be,” you will ask me to define “being.” If I say that “to happen” means “to do,” you will ask me to define “doing.” And so on.

The meanings of such basic concepts seem elusive because they are recursive, yet they are simple because they are self-evident: they follow rather immediately from the realization that the universe is objectively real, and needs no help from anyone to be what it is. Otherwise physics is completely vacuous and pointless.

For example, to paraphrase Webster’s Dictionary, “to exist” means “to be an entity,” and “entity” means “that which exists.” To prevent this from being circular, we must respect the termination condition of the recursion: we have to stop at the point where the epistemological primitives become self-evident.

That is to say, this could go on forever, so I think I’ll stop now.

In any case, I enjoy your blog and may well stop by to chat again sometime.

To be is to do – Immanuel Kant
To do is to be – Jean-Paul Sartre
Do be do be do – Frank Sinatra

Bee said...

Anonymous,

All I am saying in this post is if you don't clarify what you mean with existence and how it relates to Minkowski space-time you can't construct any disagreement - it's a waste of time. If you argue one can't define existence, that's fine with me, but then you can't expect Special Relativity to help you with the details. I am tempted to say 'existence' doesn't have any meaning except for what we think it does. That's fine with me, but then one shouldn't try to go beyond that and promote it to something fundamental.

they follow rather immediately from the realization that the universe is objectively real, and needs no help from anyone to be what it is.

Well, for one that's a realization at least I haven't had. But besides this you again fail to notice that this doesn't and can not tell you anything about the question whether the past or the future exists in the same way as the present. You seem to be assuming that because YOU think the present to be different it has to be different. What I am saying is that this is very obviously a subjective experience that one shouldn't trust.

Anyway, I am repeating myself, so I think I'll leave it at this.

Best,

B.

Anonymous said...

Bee:

In response to my statement that the universe is objectively real, you write, “that's a realization at least I haven't had.” Now the source of the disconnect is very clear to me.

But I have to ask you... if you don’t believe that the universe is objectively real, then why would you ever want to study physics?

Bee said...

It doesn't matter whether it's real, it only matters whether it can be described by our theories. Questions of what reality is, what existence means, or whether we do 'discover' or 'invent' theories and so on I leave to the philosophers. It's not that I regard them uninteresting (if you read my blog frequently you should have noticed) I just don't like people to pretend one is the other. If somebody wants to philosophize whether the multiverse is 'real', fine. But he or she shouldn't pretend that's physics. If somebody want's to philosophize what the block universe implies for our notion of existence, fine. But then he shouldn't pretend that's got something to do with physics.

Anonymous said...

Bee:

To me, internal consistency just isn’t enough. The Ptolemaic system of epicycles is internally consistent. Solipsism is internally consistent. But science, most particularly physics, demands much more than that; it demands consistency with external, objective truth. Otherwise we would have no reason to conduct experiments.

As for the role of philosophy in physics, I can’t say it any better than Edwin Jaynes did, so here are his words on the subject:

In the construction of theories, philosophy plays somewhat the same role as scaffolding does in the construction of buildings; you need it desperately at a certain phase of the operation, but when the construction is completed, you can remove it if you wish, and the structure will stand of its own accord. This analogy is imperfect, however, because in the case of theories, the scaffolding is rarely ugly, and many will wish to retain it as part of the final structure. At the opposite extreme to this conservative attitude stands the radical positivist, who in his zeal to remove every trace of scaffolding, also tears down part of the building. Almost always, the wisest course will lie somewhere between these extremes.

Jaynes, E T, 1967: Foundations of Probability Theory and Statistical Mechanics. Delaware Seminar in the Foundations of Physics (ed. Bunge, M), 77-101, Springer-Verlag.


In any event, Bee, I certainly agree with you – wholeheartedly! – that people who pontificate about the multiverse should not pretend they are doing physics.

Bee said...

Nice quotation, I like that. No, internal consistency isn't sufficient. But one can explain observations without discussing what reality is, that's what I meant to say.

Anonymous said...

Bee:

Yes, I think Jaynes was one of the clearest thinkers among 20th century physicists. Sadly, he died in 1998.

But once again, your remark has tweaked my curiosity. If observations are not grounded in reality, then they are pure fantasy, about which physics has nothing to say. So what can it possibly mean, to a physicist, to explain observations that are divorced from reality?

Bee said...

Physics explains observations, period. It doesn't say anything about whether they are reality or what that means. If you want to call them fantasies instead, then physics obviously has to say something about fantasies, but here we are again back to the problem of words without definitions.

Anonymous said...

Bee:

Do you think, then, that physics has nothing to say about how the world works when you are not observing it? And if observations have nothing to do with reality, then what, exactly, are you observing?

Bee said...

I didn't say observations have nothing to do with reality. I said physics doesn't tell you anything about a concept called 'reality', it is about explaining observations. You can believe reality 'is' whatever you like. The question 'what' one observes doesn't make sense to me. The observation is already what one observes.

Giotis said...

Hi Bee,


Bee: "I never said 'B does not live' in the simultaneity plane"

If A and B exist in the simultaneity plane, then we are Ok i think.

In other words we have a rigid rod at rest and parallel to the X axis in your figure above. The ends of the rod have the same time in space time because this is the way inertial frames are constructed in SR i.e. the two clocks at the ends of the rod will indicate the same time. The ends of the rod are presently existing. So the notion of "presently existing" coincides with the notion of the simultaneity plane. So where is the problem? Any other existence slicing (as the surfaces you have defined) can't describe the rigid rod.

Regards

Anonymous said...

Bee:

Then why do we demand agreement, to within experimental error, when two observers observe the same property of the same object under the same conditions?

Bee said...

Hi Giotis,

A and B do not 'exist' in together (at the same τ) in the simultaneity plane. However, the very point of this post was to say that the notion of 'existence' is completely meaningless unless you define it.

Your problem is that you DO attach some specific meaning to 'existence' and you do believe it to be incompatible with mine. While I am saying without defining 'existence' you can't say anything to begin with. Your example with the rod is an attempt to say something about existence of the one end (that you can not observe) while you are sitting at the other. What I am saying is you might find it plausible that the other end 'exists' in whatever sense you mean that, but there is totally no reason for why this has to be the case especially not because you haven't explained what you mean with existence.

Best,

B.

Bee said...

Hi Anonymous,

Then why do we demand agreement, to within experimental error, when two observers observe the same property of the same object under the same conditions?

Because it has shown it works well to improve our theories that way. I don't know what you are aiming at. I didn't claim two observers would observe different things, that's not what experience tells us (restrictions apply). You might ask however whether there 'exist' two observers to begin with ;-) Best,

B.

Anonymous said...

Bee:

So, we agree that experience tells us that any two observers, who observe the same property of the same object under the same conditions, must necessarily agree on the content of their observations to within experimental error. There is only one plausible explanation that can account for this: the property, the object and the conditions must be objectively real, and exist independently of any observer.

This conclusion is inescapable as long as at least two observers exist. And if less than two observers exist... well, then I am enjoying a cordial debate with a figment of my imagination...

Giotis said...

Hi Bee,

You are killing me :-)

When i say exist in SR i mean exist in space time. We can assign to something that exist a t,x,y,z or a t,x in your figure, otherwise it doesn't exist.

The only thing that i have postulated in my previous post was that the two ends of the rod are existing. This means that if one end (the one i am observing or measuring) exists then the other end exists too.

You can say that what i have postulated is not true:

So you can say that the other end of the rigid rod does not exist. But a nice property of the rigid rod is that it doesn't have one other end. You can cut it in the middle and you still have a rigid rod. You can continue this process as long as you like. In other words if you have one end of the rod then you are SURE that there is another end. This other end has to belong to the simultaneity plane of "my" end which i am sure that exists. There is no other option. So you can be sure about existence (i.e. that something occupies a space time point) not only in one point of space-time (HERE and NOW) but also (and only there) in the simultaneity plane of that point. So presently existing can only be defined through the simultaneity plane. Any other existence slicing (as the ones in your figure for example) can't describe the rigid rod. Moreover if we are sure that something that exists belongs to one existence slicing (the simultaneity plane) can't belong to another too.


Regards

Andrew Thomas said...

Giotis, you don't know the other end of the rod exists until you either take a look at it (in which case, you're actually looking at how it existed a fraction of a second ago) or you pull the rod in and have a feel of the end (in which case, you're finding out what the end is like now, not how it was earlier - which is what you really wanted to know). Either way, you can't tell what the other end is doing **right now** if you're holding the opposite end.

But the whole rod thing is a red herring. You can only be sure of the reality of something which is both here and now. You know nothing about the reality of the other end of the rod right now, really. It could be anything.

Someone told me, if the sun disappeared instantly, we'd still be orbiting it for seven minutes. Because planet earth has no way of knowing what the sun is doing **right now**.

Giotis said...

Hi Andrew,

The point is that i don't care what is happening at the other end of the rod; the only thing that i care for is that another end has to exist i.e. it must occupies a point in 4D spacetime. There is no other way unless there are more dimensions of course. But then this is not SR. If another end does not exist then we are at the same space-time point, the one we are measuring.

I know that is seems like a red herring but i think the example has a logical base.

Regards

Giotis said...

Andrew, if you mean that there is an observer at the one end and does not know that this is a rigid rod then you are right of course but then the whole thing is pointless i guess.

Regards

Plato said...

Simply Connected

As to living on a sphere or a torus.

As I was reading I came upon a fishing analogy that might be beyond the comprehension of some.

Imagine living on a manifold, and making a trip from some point. We make sure we attach a string to a firm stake to a starting point. If we pause at some intermediate point of this journey, and try to reel in the string from where we are, it will pull taut held at it's other end by it's stake. The string wil trace a direct path from where we stopped to the point where we started(and measuring the length of the string would give you the exact distance between the starting point and stopping points)

Such mapping would lead to the understanding and distinctions of whether one is on the torus, or, the sphere.

Whether we thought of "amplitudes" would be beside the point, since, we are talking about something that is fiction.:)

The point is, using the imagination, such thoughts regarding such micro-standards are assumptions about the universe, and people will even reject the mathematical basis of what these insights incur to explaining anything about our universe. Who would ever thought such distinctions and determination would ask that we realize where we are by determining our place on a geographical map. A two dimensional realization of a torus, and for a sphere, global realizations. It's all new to me.

I forgot myself for a moment there, and in a recursive moment returned to my primitive self. I'd hoped that wouldn't be self-evident?:)

White false teeth:):)

Giotis said...

An addition to the above:

What i wanted to show with the rigid rod example basically, was not that the other end has to exist but if it exists (occupies a point in space time) it has to belong to the simultaneity plane of the one end. It can't belong to any other existence slicing. Whether rigid rods exist or not you can derive it from experiment.
So if i say based on physical experiment that rigid rods exist then the argument is still valid.

Regards

Andrew Thomas said...

Hi Giotis, yes, if you are a stationary observer equidistant from the two ends of the rod then they do belong in the same plane of simultaneity for you. In simple terms, light from the two ends of the rod reaches you simultaneously. If, say, both ends of the rod catch fire at the same time you will see them both simultaneously.

In this case, and in this case only, the plane of simultaneity and the absolute, universe-wide plane of existence are the same thing.

But then you say "It can't belong to any other existence slicing". Well, if you were, in fact, a moving observer then the two ends of the stick catching fire would no longer be in the same plane of simultaneity for you - you would no longer see the two ends catching fire at the same time. But in the existence plane, nothing has changed - in universe-wide absolute cosmic time the two ends of the stick still catch fire at precisely the same time. So your plane of simultaneity and the absolute plane of existence no longer correspond.

I'm not quite what you're saying about your rigid rod existing before and after, but the impression I get is that you're saying "if you know you're dealing with a rigid rod, and you know one end exists, then you know the other end exists". Well, you don't really. As I've just suggested, for all you know the other end could be on fire. It's like the sun that vanishes and we keep orbiting. You don't know about existence unless it's here and now.

Bee said...

Hi Giotis,

When i say exist in SR i mean exist in space time. We can assign to something that exist a t,x,y,z or a t,x in your figure, otherwise it doesn't exist.

Well, then you have just defined everything in Minkowski space to 'exist', which is the block universe view. And no, this definition of 'existence' is not identical what I was talking about, since I set up to give you an example in which you have a 'sliced' notion of existence (thus a present moment) and not a block universe. This post is supposed to tell you that this can still be compatible with SR. It is of course not compatible with the block universe view. I think the problem is that you have a preconceived notion of 'existence' that you are clinging to despite there being to reason for it. As Andrew explained above, there is no way you can tell something 'exists' on your slice (i.e. 'now') without it also being 'here'.

Best,

B.

Bee said...

Hi Anonymous,

So, we agree that experience tells us that any two observers, who observe the same property of the same object under the same conditions, must necessarily agree on the content of their observations to within experimental error.

I do not see how why they 'must necessarily agree' and this is not what I said. Experience tells me they generally do, and I have no reason to expect otherwise, but this is far off saying this must necessarily be the case.

There is only one plausible explanation that can account for this: the property, the object and the conditions must be objectively real, and exist independently of any observer.

This conclusion is inescapable as long as at least two observers exist. And if less than two observers exist... well, then I am enjoying a cordial debate with a figment of my imagination...


This conclusion is very escapable as it simply is no conclusion. You are making the same mistake over and over again. You have no definition for what it means to be 'objectively real', therefore you can't conclude anything about it. You can go and define something as 'objectively real' iff 'all people we've asked agree with their observations on it', but then this is just a definition.

Whether or not you find that 'plausible' is a completely different point. I am not saying that an external reality is implausible, and I certainly notice that most people seem to find it very plausible, I am just saying there is no way to prove this view is de facto true.

Best,

B.

Anonymous said...

Bee:

Something is objectively real if and only if it keeps on being what it is and doing what it does, no matter who is looking, and indeed, even when no one is looking. That is to say, “objective reality” means “observer-independent repeatability”. I think I have stated this clearly, several times, in several different ways.

If you disagree with this definition, perhaps you can suggest your own?

Now, this definition immediately leads to a procedure for testing whether something is objectively real: we have independent observers observe it and we note whether the results are consistent. We have various observers repeat the observations until the evidence has accumulated to whatever level will convince us that observer-independent repeatability does or does not hold. Of course, we can never get to 100% certainty this way, just as we can never achieve 100% accuracy in our observations, but we can get close enough for any conceivable purpose.

Note that this is precisely the procedure universally followed, not only in experimental physics, but also in every other experimental science. Yet, regarding observer-independent repeatability, you say you “have no reason to expect otherwise, but this is far off saying this must necessarily be the case.”

How, then, do you suggest we go about comparing and resolving the validity of a set of conflicting observations?

Andrew Thomas said...

I think without knowing what existence actually **is** (what is a particle, exactly?) we can still suggest properties which all physically real "stuff" should have. And yes, as you suggest, I think it has to be independent of observation. It has to be possible to be "objective" about it, to say that something is "out there" and for people to agree what it's like. I remember reading about "objective physical reality, independent of observation", and I think that's the best definition of "reality" or "existence" I've come across.

Einstein gave that quote: ""If, without in any way disturbing a system, we can predict with certainty the value of a physical quantity, then there exists an element of physical reality corresponding to this physical quantity.", basically attacking quantum theory: If a physical property of an object can be known without it being observed, then that property could not have been created by observation. If it wasn't created by observation, it must have existed as a physical reality before its observation.

Plato said...

I thought I would add my "two bits"
to the issue of the "Plane of Simultaneity"

The world line had to have some explanation to it, so it had to be correlated in my mind to the current experimental technologies.

Oh and using this box for comment has a deeper relevance then just the place words go, and thusly, this event(comment) becomes solidified as we click our way into reality. The idea here is, that the world we enter into is not real as these words or anyone else's pour forth?:)

When, and if I die( by assumption this eventually happens) I will come back to "such a box" for clarifications:)

Plato said...

Oh, I hope one can appreciate "the humour" of that previous post "by proxy":)

Anonymous said...

andrew:

Yes, I agree; it is hard to imagine a satisfactory definition of reality that doesn’t involve observer-independence. I’m curious to see what Bee comes up with...

Regarding Einstein, I don’t think he was attacking quantum theory as such. Rather, he was criticizing – quite rightly, in my view – the magical, mystical overtones of the Copenhagen interpretation of quantum theory.

There is no doubt that quantum theory is correct, in the sense that we will never prove it wrong – though we should do our best to refine it and extend it, just as quantum theory refines and extends classical physics. But before we can do that, we will have to come to terms with the difficulties of forming a consistent description of objective reality, when all we have to work with are subjective impressions of it.

Andrew Thomas said...

Oops, you're right. I meant the Copenhagen Inerpretation.

Bee said...

Hi Anonymous,

Yes, I agree; it is hard to imagine a satisfactory definition of reality that doesn’t involve observer-independence. I’m curious to see what Bee comes up with...

? I have the strong impression we are talking totally past each other. You are the one who is talking about `reality' whereas I tell you I can't even agree or disagree on what you say unless you define what you mean with that. I never even remotely indicated I have a definition for `reality' or the desire to come up with one, I just tried to find out what you are talking about.

You say

Something is objectively real if and only if it keeps on being what it is and doing what it does, no matter who is looking, and indeed, even when no one is looking [...] I think I have stated this clearly, several times, in several different ways.



a) We never know there is a 'something', we only have observations. If you want to go with Plato, all we ever see are the shadows. You can use 'somethings' as explanations that are more or less plausible or useful.

b) If you are using such a 'something' but it isn't observed there's no point in saying it is there or is not there, as this question is by definition undecidable (I don't mean 'observation' in the operational QM sense, there are some subtleties to this).

“objective reality” means “observer-independent repeatability”

Okay, thanks, if you have defined it this way, then what is your problem with my attitude? I explained you above that I certainly agree that observer-independent-repeatability is well established. This is exactly the reason why science works, and that's all one needs to know. Everything else is baggage.

If you scroll back up to find out where this discussion came from you'll find that all I said was that physics isn't concerned with arguing about what `reality' or `existence' means, but with explaining observations.

Best,

B.

Anonymous said...

Bee:

My point is that there can only be two causes for “observer-independent repeatability” of observations: either we are observing the same thing, something that exists separate from all of us, or we are all deluded in exactly the same way. In the latter case, physics is pointless and without content or value. Fortunately, as the number of independent observers increases, this latter case becomes overwhelmingly unlikely. Therefore I conclude that the former must be the case. Namely, that something exists separate for all of us, and that it is precisely that something which is the subject matter of physics.

I hold this to be true for the same reason that I hold the second law of thermodynamics to be true. Not because is can be proven in the all-or-nothing sense of Aristotelian syllogism, but because the converse is so overwhelmingly unlikely that it would be foolish to entertain it.

Something about this line of reasoning doesn’t sit well with you, and I can’t figure out what it is...

Anonymous said...

Correction: "seperate for all of us" should read "serperate from all of us" in my previous post.

Anonymous said...

Correction to the correction (sheesh!):

"separate from all of us"

That's how it should read.

Bee said...

Hi Anonymous,

We're just running in circles, that can't possibly be so hard to understand what I am saying? I asked you to explain what you mean with 'real' (and I think with 'exist' you mean the same as 'to be real'). You explained

Something is objectively real if and only if it keeps on being what it is and doing what it does, no matter who is looking, and indeed, even when no one is looking

Now you say

there can only be two causes for “observer-independent repeatability” of observations

A definition doesn't need a cause, it's a definition. If you don't have a definition, your statement is empty.

Both 'causes' would imply the same 'reality' because that's how you have defined 'reality'.

Further

this latter case becomes overwhelmingly unlikely. Therefore I conclude

Saying something is unlikely, especially without quantifying it or at least giving a reason, is not the same as drawing a conclusion.

In essence what you are saying repeatedly is what I already acknowledged above. You find it plausible there is an external reality, something that 'exists' if it is not observed and so on. Many people believe that. I have no objections to this. I just don't seem to find it as plausible as you, but my opinion on that changes with the weather and the moon phase. What I am trying to tell you is that this question is not decidable, but for physics it totally doesn't matter what reality 'is' or what you think is plausible.

Best,

B.

Plato said...

After meeting in mind Glaucon by proxy, I was convinced that "environmental scanning" had served it's purpose by by making these assumptions that I do, do a disservice to people by assuming they know what I know?:)

So by such a "meeting of minds" which serves to enhance and further develope perspective, (that's what blog work is meant to do in my thinking,) then it was also important that when looking at the plane of simultaneity to considier this in context of the immediate effect of the sun with the results of SNO.

In Galactic Communications it couldn't be otherwise. Anyone want to start a new company?:)

Plato said...

In context of the plane of simultaneity, it must be recognized that such a proposition was introduced to also support tachyon illustrations with "faster then light" entities. This would be placed in context of Penrose's quanglement issues and his new world view.

Somebody had to write in support of it?:)

Anonymous said...

Bee:

Nothing about reality is decidable, in the sense of the word as used in formal logic. But that doesn’t mean these questions are so weakly determined as to justify changing your opinion “with the weather and the moon phase.”

When you say that the existence of objective reality is merely “plausible,” your choice of wording implies (whether you mean to or not) that the evidence is not particularly compelling, one way or the other. On the contrary, I say that the balance of the evidence is so compelling that it makes the assertion overwhelmingly likely.

I am beginning to suspect that you are reluctant accept this latter statement because, as a theoretician, you are inclined to consider whatever cannot be proven by formal logic to be completely indeterminate. But I must caution you against indulging such inclinations.

Bee, one doesn’t bring a knife to a gunfight for the same reason that one doesn’t limit oneself to deductive formal logic in a situation that demands inductive inference: the tool is inadequate in the context. By “inductive inference,” I don’t mean “mathematical induction,” because this is actually just another form of deductive inference. What I mean is the following:

When evidence is subject to experimental error -- and indeed can be missing altogether -- then the idea that a hypothesis, H, follows from the evidence, E, by logical implication,

E => H,

is inadequate. One must generalize it, using the concept of conditional probability, to

P(H | E) >= theta,

where theta is the threshold at which we decide that the evidence is sufficient to warrant treating the conclusion as true. When we set theta = 1, we recover logical implication. But when reasoning about the real world, this is never justified.

Impalatable though it may be to a theoretician, one must set theta based on practical considerations, such as the cost of being wrong. And one must always remain open to the eventuality that things may not be as they seem. As Whitehead reminds us in the preface to his Dialogues:

There are no whole truths; all truths are half-truths. It is trying to treat them as whole truths that plays the devil.

Andrew Thomas said...

Very interesting post, Anonymous (who are you? Come clean!). I've often wondered if the whole concept of logical statements being either "true" or "false" just has no relevance to physical reality because we can never be absolutely sure of anything! And how does this tie in with quantum indeterminacy? I dunno - it's all very philosophical.

Andrew Thomas said...

It's a fair bet you come from a philosophy background rather than a physics background, yes?

Bee said...

Hi Anonymous,

Nothing about reality is decidable, in the sense of the word as used in formal logic.

I think you are finally understanding what I say. All I have pointed out re-repeatedly is that your claims that things are 'provable' or conclusions that follow are not proofs, or are not conclusions. And yes, when I say so, I am talking about formal logic. If I may come back to the topic of this post, I was trying to explain that Petkov does not 'show' (in the sense of proof) what he claims he does. You are still free to believe or not to believe in the block universe depending on how 'plausible' you think it is.

What I have also said re-repeatedly is that it doesn't matter for physics what 'reality' or 'existence' means, therefore this questions isn't part of physics and falls into the realm of philosophy. I have therefore a limited interest in pondering the question exactly because it is undecidable.

But that doesn’t mean these questions are so weakly determined as to justify changing your opinion “with the weather and the moon phase.”

When you say that the existence of objective reality is merely “plausible,” your choice of wording implies (whether you mean to or not) that the evidence is not particularly compelling, one way or the other. On the contrary, I say that the balance of the evidence is so compelling that it makes the assertion overwhelmingly likely.


To repeat what I said before, you are using terms like 'overwhelmingly unlikely' and 'weakly determined' without any justification other than your personal preferences (and probably the knowledge that the vast majority of people on this planet share your beliefs on this matter). You'd have a hard time proving even that an external reality is the most likely explanation for our experiences.

Best,

B.

Anonymous said...

Bee:

You have the definition of physics and philosophy backwards! When physics is unconcerned with objective reality, it reduces to solipsism, and thereby it ceases to be physics and becomes philosophy.

I think you ought to consider more carefully the part of my previous post that talks about inductive inference. As I suggested before, think of it in terms of the arguments one uses in support of the second law of thermodynamics. The second law can’t be proved deductively, but that doesn’t mean that it is “without any justification other than [one’s] personal preferences.”

It is a logical fallacy to hold that whatever cannot be deduced is completely indeterminate. The difference in force between a deductive inference and an inductive inference can be mare arbitrarily small, given sufficient evidence.


andrew:

Actually, I am a physicist turned computer scientist… although, in essence, they are the same.

Phil Warnell said...

Hi Anonymous,

“It is a logical fallacy to hold that whatever cannot be deduced is completely indeterminate. The difference in force between a deductive inference and an inductive inference can be mare arbitrarily small, given sufficient evidence.”

To infer is to deduce, so in my view the difference is that in inductive inference you substitute observation as to be the premise. I think the sticking point therefore is that when reliable observation(s) can only be practically taken from ones own frame of reference, what else could be reasonably considered as to be the premise?

Best,

Phil

Plato said...

Mathematics is not the rigid and rigidity-producing schema that the layman thinks it is; rather, in it we find ourselves at that meeting point of constraint and freedom that is the very essence of human nature. Hermann Weyl

Under the "Aristotelean Arch" what is real? "Self Evident" is at the peak of reasoning, and after an inductive/deductive exchange being internalized, so is the search for the mathematics to explain the process?

Hmmm... does this sound familiar? Do you catch yourself doing this?

An Alternative then

String theory may then be used when focused on( to those who joke well ....), it still becomes an interesting option. Who would have ever thought "hills and valleys(a false vacuum to the true)" could have meant anything to Lee Smolin?:)Did it?

Superstring theory is most relevant under extreme physical conditions such as those that existed at the time of the big bang. Recently, we have formed a new institute at Columbia called ISCAP (Institute for Strings, Cosmology, and Astroparticle Physics) dedicated to understanding the interface of superstring theory and cosmology. One primary focus of ISCAP is the search for subtle signatures of string theory that may be imprinted in the precision cosmological data that will be collected through a variety of experiments over the next decade.

Lee seems to have moved on, or, just had other things he wanted to make known. A different way about him one might say? And Glast, shall it light the way, while the pursuant of thinking "outside of the box(glast)" goes on:):)

G -> H -> ... -> SU(3) x SU(2) x U(1) -> SU(3) x U(1)

Here, each arrow represents a symmetry breaking phase transition where matter changes form and the groups - G, H, SU(3), etc. - represent the different types of matter, specifically the symmetries that the matter exhibits and they are associated with the different fundamental forces of nature

Bla Bla:)

Plato said...

Physically, the effect can be interpreted as an object moving from the "false vacuum" (where = 0) to the more stable "true vacuum" (where = v). Gravitationally, it is similar to the more familiar case of moving from the hilltop to the valley. In the case of Higgs field, the transformation is accompanied with a "phase change", which endows mass to some of the particles.

You just had to keep the process in context as you explore the potentials of expression. Think about the nature of the universe in expression.

Subtle insights as to the explanations are imbued with neutrino implications while the talk is still about photons and such.

Casting a light over it all, is geometrical explanation as to what forms shall exist in the valleys?

Of course these contain entropic valuations and complexities about the current state of our universe, but still, we are directing our attention to what is real?

So one goes off on some "theoretical bend" how real is that?

Bee said...

Hi Anonymous,

It is a logical fallacy to hold that whatever cannot be deduced is completely indeterminate.

I did not say it is indeterminate, I said it is undecidable. You can never proof that there 'is' something you can't observe because you can't observe it. That doesn't necessarily mean that (if you set up the question appropriately) the answer is indeterminate.

You have the definition of physics and philosophy backwards! When physics is unconcerned with objective reality, it reduces to solipsism, and thereby it ceases to be physics and becomes philosophy.

As I said repeatedly, physics is concerned with observations. It does not care whether 'reality' 'is' or 'is objective' or is any other word.
How often have I now told you that this statement is empty if you don't consider what you mean with 'objective reality'? Upon my inquiry, you above defined it as
“observer-independent repeatability”
and I have already told you repeatedly that yes, I acknowledge, that this is the reason why physics works so well. Criteria you might want to attribute to 'objective reality' that are not observable do not fall into the realm of physics, that's what I'm saying.

I think you ought to consider more carefully the part of my previous post that talks about inductive inference. As I suggested before, think of it in terms of the arguments one uses in support of the second law of thermodynamics. The second law can’t be proved deductively, but that doesn’t mean that it is “without any justification other than [one’s] personal preferences.”

I too think you ought to consider what I said above. The second law of thermodynamics can be shown to hold with very good probability under certain circumstances, and it is backed up with an almost infinite amount of observations. In contrast to this, you are claiming something is likely without having any way to backup this likeliness since you are talking about a matter that is undecidable in every single instant. You have not a single observation confirming something 'exists' if you don't observe it because that's by construction not possible. The only thing you ever have are observations. That can't possibly be so hard to understand.

Best,

B.

Andrew Thomas said...

Roger Penrose described all this "reality" and "existence" stuff superbly in "The Road to Reality" (when he considered the quantum wavefunction):

"Let us step back from these detailed matters for a moment, and ask what all this is trying to tell us about 'reality'. Are the dynamical variables 'real things'? Are the states 'real'? Or should we say that we have achieved reality only when we have arrived at the seemingly 'classical' quantities that arise as eigenvalues of the dynamical variables (or of other operators)? In fact, quantum physicists tend not to be very clear about this issue. Most of them are distinctly uncomfortable about addressing the issue of 'reality' at all. They may claim to take what they would call a 'positivist' stand, and refuse to consider what 'reality' is supposed to mean, regarding such an inquiry as 'unscientific'. All that we should ask of our formalism, they might claim, would be that it gives answers to appropriate questions that we may pose of a system, and that those answers agree with observational fact.

If we are to believe that any one thing in the quantum formulation is actually 'real', for a quantum system, then I think that it has to be the wavefunction (or state vector) that describes quantum reality. My own viewpoint is that the question of 'reality' must be addressed in quantum mechanics - especially if one takes the view (as many physicists appear to) that the quantum formalism applies universally to the whole of physics - for then, if there is no quantum reality, there can be no reality at any level (all levels being quantum levels, on this view). To me, it makes no sense to deny reality altogether in this way. We need a notion of physical reality, even if only a provisional or approximate one, for without it our objective universe, and then the whole of science, simply evaporates before our contemplative gaze!"

Bee said...

Thanks for the quotation. Yes, he said that very aptly.

Anonymous said...

Bee:

I am beginning to wonder what you think an “observation” is. You write “you have not a single observation confirming something ‘exists’ if you don't observe it,” which is obviously true, but completely irrelevant, because we do observe it. Every observation consists of information about externally existing objective reality (mixed with noise). If you disagree with this, then what do you think observations are about?


Plato:

Great quote from Hermann Weyl!

Anonymous said...

Bee:

Given your stance up to this point, it seems incredible that you agree with the Penrose quote posted by andrew. The last part says

it makes no sense to deny reality altogether in this way. We need a notion of physical reality, even if only a provisional or approximate one, for without it our objective universe, and then the whole of science, simply evaporates before our contemplative gaze!

And this is precisely the point I have been making!

Bee said...

Anonymous:

it seems incredible that you agree with the Penrose quote [...] And this is precisely the point I have been making!

I can read. I know what the quote says. I did not say I agree, I said Penrose expressed that very aptly. I also know what you are saying. You said it less aptly. In contrast to you however Penrose says very carefully "To me, it makes no sense...". You left out the words "To me". It is obvious that to you it doesn't make sense what I say, so why don't we just leave it at this. I honestly see no point in this discussion. You simply do not want to understand my point of view, despite the fact that you've agreed there is no way to decide whether one of us is right or the other wrong.

Bee said...

Anonymous:

I am beginning to wonder what you think an “observation” is. [...] Every observation consists of information about externally existing objective reality (mixed with noise). If you disagree with this, then what do you think observations are about?

We have already had this exchange above, so I'll just repeat: The question 'what' one observes doesn't make sense to me. The observation is already what one observes.

Anonymous said...

Bee:

Recall that “to observe” is a transitive verb. It is what the observer does to the observed. Thus it is not semantically well formed to speak of an observation which does not refer to anything. You may as well ask, “what is the difference between a duck?”

If you nonetheless choose to treat your observations as things in themselves, not as carriers of information about something outside yourself which is observed, then you have retreated into solipsism, so there is no way to reach you.

Bee said...

Hi Anonymous,

Thus it is not semantically well formed to speak of an observation which does not refer to anything.

If you're interested in the question as to how the way we use language can influence how we think about our world, I recommend one of the first chapters of Bohm's book "Wholeness and the Implicate Order" (can't say I really understood it, but it's definitely interesting.)

Anyway, besides this I have no clue what this sentence is supposed to say.

I don't care much which ism you want to attribute to me. It is certainly the case that single brain that I am, the only thing I can ever be sure of is that I exist, sad but true - yet you will find if you read through this thread that I never said I believe this to be the case. Instead what I've tried to say is that physics doesn't care one way or the other, what reality is, whether things 'really exist' or what that means to begin with, as long as observations are described by our theories. Best,

B.

Giotis said...

Hello Bee, How are you?

I will attempt another post on this subject to explain my position a little better.

I never wanted to define existence or anything like that or to say anything about the block universe. The conversation was deviated from its original context. My intention was to show that what you said:

"there is no reason to define 'presently existing' with the surfaces of simultaneity in SR."

cannot be true in my opinion and there is a reason after all to choose simultaneity planes.

You also didn't define existence but you connected existence with a "now", but you defined this "now" not with the simultaneity plane but with another absolute surface:

"Since I do not want to define 'existence' either, I too want to export it into the 'now'".


also:

"there is no reason why the 'existence' should be bound to the 'now' in the way one can define it in SR".

That is why you defined another "now".


and later:

"To see this, put an 'existence - slicing' with a time parameter t on Minkowski-space [4] and say for each t it is only the respective slice that 'exists', or is 'now' - according to this definition of 'now'".


What i am saying is that we can't define this alternative now. A "now" can only be understood via the simultaneity plane in SR.

That is why i have used the rigid rod example and the one with the synchronization of the two scientists in an earlier post if you remember. If you mound a number of clocks on a rigid rod, at rest in its own frame you can always synchronize them in SR to indicate the same time. If you put v=0 in a lorentz transform you will get t1=t2=t3 etc. With your surfaces you can never achieve synchronization for these clocks even if the rigid rod is in its rest frame. No matter what you do: t1 # t2 # t3 etc.

What is our simultaneity plane? It is the locus of events/observers each of whom is at rest relative to each other and us. The time they report should always be the same with our time. Synchronization is not lost for events/observers at rest. On the contrary with your surfaces the observers at rest will never report the same time. Synchronization is lost in general even for observers at rest and SR does not permit that. In SR you can always have a set of observers who agree with us regarding the simultaneity of events. These are exactly the observers who are at rest relative to us and each other.

That is why in text books an inertial frame is depicted with a continuum of observers at rest relative to the others or with clocks held together by rigid rods. Because this is the only way we can keep the synchronization.

So my natural conclusion is that you can't define other "now" surfaces in SR.


I don't say that is mandatory to connect existence with "now" because existence indeed is an ambiguous philosophical term. But if you connect it with a "now" that now can't be other than the "now" defined by the simultaneity plane. Any other surface is prohibited in SR.

So if you say that something exists now. This now is the now defined via your simultaneity plane. Any other "now" does not fit in your inertial frame as this can be understood in the context of SR.

You on the other hand say that this now could be defined with another absolute surface. Thus, you also defines existence with a "now" but of a different kind. (Bee correct me if i am wrong).

Of course you can always say that i can't connect existence with a "now" because i don't know what existence is. That is acceptable but then you don't need any imaginary "now" surfaces to prove anything.

Bottom line:

According to my understanding the simultaneity plane is not something artificial in SR which can be removed just like that and replaced by another absolute "now" surface. It represents something natural, that observers/events at rest relative to each other should agree on the simultaneity of events and should be able to synchronize their clocks to report the same time with us. In SR you can always find such a set of observers who agree on the synchronization of events otherwise an inertial frame cannot be constructed.

Any other absolute "now" surface like the one you defined will be intersected by the world lines of events/observers at rest relative to each other, at different times and synchronization will be lost. Observers at rest will never agree on what is now. That is not acceptable in my opinion.


Regards

Phil Warnell said...

Hi Bee,

“If you're interested in the question as to how the way we use language can influence how we think about our world, I recommend one of the first chapters of Bohm's book "Wholeness and the Implicate Order" (can't say I really understood it, but it's definitely interesting.)”

Not that it carries much weight, yet at least for me this serves to indicate that you certainly do have an open mind. For as I see it, Bohm, Bell and some others , even if they are proven to have accomplished nothing else, still would be valued as to have taught and insisted this to be a required concern and consideration.

Best,

Phil

Andrew Thomas said...

I actually thought the Penrose quote supported both Bee's and Anonymous's positions (which is why I posted it). Bee takes the viewpoint of the majority of physicists "regarding such an inquiry as 'unscientific'", while Anonymous agrees with Penrose more. It's not a case of right and wrong - just two different viewpoints.

Bee said...

Hi Giotis,

What you are saying is that you like the definition of a 'now' in SR because it seems plausible to you. You do not like any other definition of a now because it does not come with a definition you like, or call it a construction plan. Yet, plausibility or construction plans are not a requirement I've asked for. You can define arbitrary coordinate slicings in Minkowski space. Just start with (x,t) and put whatever (well-defined) coordinate transformation to (ξ,τ) on it. That's a new definition for a time, and it defines a new slicing. In flat space it seems there are compelling reasons to chose specifically Minkowski-coordinates (up to a Lorentz-trafo) because these are the free-falling frames of inertial observers. Maybe it helps to the understanding if you consider that in curved space it's far less obvious which slicing is the 'right' one. Some slicing are nicer, some less nice, but they are all equally good. Also, you can very well have a slicing with preferred restframes (as I indicated in the last paragraph). Best,

B.

Bee said...

Hi Andrew,

Yes, thanks, that's how I understood it. I guess though Penrose is primarily concerned with a different question than the one discussed in this post - in the quote he seems to be referring to the question of 'reality' in quantum mechanics. This is another topic one can excellently and eternally argue about. Anyway, I hope I made clear that I do regard these questions interesting and also relevant to physics (as I have e.g. expressed here), I just don't like them to get mixed up. If somebody wants to do philosophy (e.g. of multiverses of whatever version) fine, but he shouldn't call it physics. I don't mind if people want to express their point of view, and I have no problem if that pov differs from mine but I don't like if somebody claims to 'proof', 'show' or 'conclude' something even though there's no proof. If I say that's a question science can't answer that doesn't mean I dismiss it or I want to say one should dismiss it. In that sense, I don't feel represented by the first paragraph of Penrose's quote. Best,

B.

Bee said...

Hi Phil,

Yeah, Bohms book is insofar interesting as that he's aiming at creating a whole world view that comes with its own philosophy and embraces much more than physics. I sometimes wonder whatever happened to these aspirations to understand the big picture. They seems to get lost the more specialization we have, whether you look into the natural sciences or humanistics. One finds glimpses of this attempt to create a larger world view in Lee's first book, and also in Homer-Dixon's books. I think also Stu Kaufman's book (At Home in the Universe) goes into this direction (but it's hard to say because I got stuck on page 50 or so). I probably should read Penrose's book, it just looks so discouraging in all its width ;-)

Best,

B.

Giotis said...

Bee:"In flat space it seems there are compelling reasons to chose specifically Minkowski-coordinates (up to a Lorentz-trafo) because these are the free-falling frames of inertial observers"

Yes i agree with that. That is what i was trying to say.

Regards

Phil Warnell said...

Hi Bee,

“I sometimes wonder whatever happened to these aspirations to understand the big picture. They seems to get lost the more specialization we have, whether you look into the natural sciences or humanistics.”

Yes I have the same complaint. If one is to realize that with Bohm and Bell gone what’s left in this regard is very little. In Smolin’s Three Roads I get the impression he feels the same. Yes we have Witten and his vision yet it for me presents to be pretty sterile. From the limited view I have of all this many of your counterparts harkens back to the “shut up a calculate” culture of the 50’s and 60’s.

“I probably should read Penrose's book, it just looks so discouraging in all its width ;-)”


Of course you know this also is a question of perspective. If you stand it in your bookshelf it is it’s width that is intimidating, yet as I was telling Andrew my copy remains still off the shelf and on the table, so what presents to be the problem is its depth:-). I can tell you one thing if considered pound for pound it has no equal. Not a subway or air flight book for sure.

Actually I have found one don't so much read Penrose's book yet rather chew on it:-)


Best,

Phil

Anonymous said...

Bee:

You are willing to accept “can be shown to hold with very good probability under certain circumstances, and it is backed up with an almost infinite amount of observations” as a method of establishing the second law of thermodynamics, but not as a method of establishing the existence of an external reality. The only difference is that in the latter case, we must delete the qualification, “under certain circumstances.” So why do you would accept the former but not the latter?

I agree completely that “the only thing you ever have are observations.” It is your insistence that observations do not describe anything outside yourself that I disagree with.

And what makes you think the question of reality in quantum mechanics is any different from the question of reality under discussion in this thread? There is only one reality. Quantum mechanics is just a formalism we use to describe certain aspects of it.

Bee said...

Anonymous:

And what makes you think the question of reality in quantum mechanics is any different from the question of reality under discussion in this thread?

What I said was: "I guess though Penrose is primarily concerned with a different question than the one discussed in this post - in the quote he seems to be referring to the question of 'reality' in quantum mechanics."

This is supposed to say: This post is about the block universe, it is neither about solipsism nor the question of what reality or existence is. I explicitly said I do not want to define 'existence, and I further stated that I here do not consider quantum mechanics.

You are willing to accept “can be shown to hold with very good probability under certain circumstances, and it is backed up with an almost infinite amount of observations” as a method of establishing the second law of thermodynamics, but not as a method of establishing the existence of an external reality. The only difference is that in the latter case, we must delete the qualification, “under certain circumstances.” So why do you would accept the former but not the latter?

I already replied to this question above. I'm getting really tired of repeating myself. You either define 'external reality' as 'observer-independent repeatability' and I have already told you, repeatedly, that observer-independent repeatability is certainly well confirmed and in fact the reason why science works so well. I certainly do not disagree on this. If you don't define 'external existence' in that or any other way, your statement is entirely empty. I also already told you that in contrast to the thermodynamic case, you do not have a single observation that 'establishes' something that can't be observed, whatever that might be.

Best,

B.

Phil Warnell said...

Hi Anonymous,

“And what makes you think the question of reality in quantum mechanics is any different from the question of reality under discussion in this thread? There is only one reality. Quantum mechanics is just a formalism we use to describe certain aspects of it.”

Just to insist that there is only one reality is the crux of your difficulty in terms of your argument, for in science to appeal to reality is fallacy. That is one cannot appeal to what one is attempting to describe. Even Einstein was dismissed on this point when using this to form part of his argument in EPR. It is one thing to hold to a conviction of what reality is, yet it certainly not to be considered science.

Best,

Phil

Plato said...

I know not how, may find their way to the minds of humanity in Some Dimensionality, and may stir up a race of rebels who shall refuse to be confined to limited Dimensionality." from Flatland, by E. A. Abbott

Well from "Plane of Simultaneity" to Penrose's book, width, it's depth(meaning) and chewing(grokking), to an appreciative stance on what the world has to offer in terms of their world views. Amazing.

What are these revolutions if one did not understand the basis of change and what was to come out of stagnation, and stunted growth.

The limits had to be identified in order to progress. If one does not understand the environment on which these things are proposed then what use to say I like this one, and this one, and not this one?

So frivolous then that we chuck aside, and because one did not understand the relationship between "the math and what is taking place in reality" how quick to take a pen and swipe a cross the page, a line, saying," oh this is, and does not make sense in the course of the events of things?"

First you really do have to understand how revolutions do take place, and secondly, how world views are constructed based on the limitations we've been taken too.

Then, while looking, one becomes intrigue by what ingenuity actually means when such a time and space presents itself, so that the creative mind can do it's thing and if it can construct according to the understanding of the limitations and introduce "a new picture" then what said that this construction cannot happen from place to place, and now, not in just one person's view.

Ingenuity then, takes on a whole new meaning, by understanding that such a space can be created. Writers present themself, and the work becomes the understanding from that world view. It's like learning a new language, and some, are better at adapting then others?:)

Some are better chewers of the depth of meaning. Some are better at assuming, as if, they are indeed, "A Stranger in a Strange land."

Now of course, some would be to young to understand this cultural significance, but some might get the point quite clearly?:)

Bee said...

Hi Phil,

Thanks. I think many people find it disturbing to notice that 'external reality' is nothing more than a believe, which is primarily backed up by other people sharing this believe (if you believe the other people 'exist' that is ;-). It is a topic though that dates back thousands of years, so it's quite interesting our Anonymous even started a discussion about it trying to come up with rational arguments that can eventually only lead to the point that he insists on believing whatever he believes and probably continues to believe, and lets me don't believe whatever I don't believe. I'm getting kind of tired with it though.

As so often, I agree with you that the scientific view that is primarily communicated today is pretty sterile. It bothers me a lot that the few people who don't stick closely to their community and try to obtain and communicate a broader view have such a difficult time. The discussion about Lee's book is to me a very sad example, as I think the vast majority of my own community did not take it seriously what he tried to say. (Instead they have been making fun of him in a rather childish attempt of defend their own ignorance.)

As to width, unfortunately my copy of Penrose's book got wet and actually temporarily increased to even double width. I've managed to squeeze it back halfways to normal format, but it looks already pretty chewed on. Either way, I have like ten other books I want to finish first... Actually, the sheer weight of Penrose's book turns out to be a hurdle, as I read a lot of books on flights, but I prefer leaner books in my hand baggage (Stupid reason I know. Time for the e-book to take off.) Best,

B.

Anonymous said...

Bee:

I keep coming back to certain points precisely because you have not answered them, only evaded them. Answer me this one question clearly and without evasion, and I will go away: if you deny that observations contain information about external, objective reality, then what do you think they contain?

And please do not repeat your statement, “the observation is already what one observes,” because every interpretation of this statement, which I can think of, is either vacuous or false.

Phil Warnell said...

Hi Bee,

“Thanks. I think many people find it disturbing to notice that 'external reality' is nothing more than a believe, which is primarily backed up by other people sharing this believe (if you believe the other people 'exist' that is ;-). It is a topic though that dates back thousands of years, so it's quite interesting our Anonymous even started a discussion about it trying to come up with rational arguments that can eventually only lead to the point that he insists on believing whatever he believes and probably continues to believe, and lets me don't believe whatever I don't believe. I'm getting kind of tired with it though.”

Yes this is very true and yet the real problem is he doesn’t even admit to it being a belief. In contrast except for the one slip that Einstein made in EPR, where he appealed to reality to be considered to form a legitimate argument, he always referred at all other times to his concept of reality as what he believes. Actually, when I raised this point with another physicist a few years back he said it was not Einstein that made this fatal error in EPR yet rather Podolsky, one of the coauthors and that he didn’t read the final draft before it was submitted for publishing. Whether if this is true or not I haven’t been able to confirm and yet it is consistent with how he expressed himself on the matter before and since that time.

“(Instead they have been making fun of him in a rather childish attempt of defend their own ignorance.)”

Actually Smolin should take this as a good sign, for as often time happens when one is subjected to such ridicule it means others find you are getting to close to exposing their own fallacies. On the other hand he did point out that people do take risk when their views don’t coincide with the consensus. He thinks they should be protected and I agree and yet fail to see how this could be done practically in our existing climate.

“ As to width, unfortunately my copy of Penrose's book got wet and actually temporarily increased to even double width. “

No kidding, really? There must be some interesting story behind this, not that would I insist it become known. It sounds though that your copy must be the paper back, for I can’t imagine the hard cover surviving such an incident. Well at least the way it now presents itself many would believe you have already read the thing, with it being so battle worn and all. One thing though with this Penrose could now claim that although his arguments may not be air tight, they have proven to be water resistant:-)

Best,

Phil

Bee said...

Hi Anonymous,

if you deny that observations contain information about external, objective reality, then what do you think they contain?

And please do not repeat your statement, “the observation is already what one observes,”


To repeat it once again, unless you define what you mean with 'external reality' I do not even know what you think I deny. Despite your attempt to define 'external reality' as 'observer-independent repeatability' I think you are in fact defending the idea that there is a 'somthing' you want to call 'external reality' that 'exists' but can not be observed - which only brings me back to the question of what does it mean for something to 'exist' and so on.

Since you don't like what I previously said, let me formulate it differently: observations are the only information we have. If you construct a 'something' because you want this information to be 'about' that something (semantics and all), then you will never have more information about that 'something' than what the observations tell you. One could thus as well say the something 'is' the information. Just that you don't like this. So, to repeat something else I said previously, you might want to think of Plato's allegory of the cave: You will never be able to see anything but the shadows (observations). You can believe, but never know, these are shadows 'of' something (external reality, fundamental truths, whatever).

every interpretation of this statement, which I can think of, is either vacuous or false.

Well, then think twice. What is vacuous is not my claim that we can not observe anything that is not observable, but your conviction that we can deduce from observations there be a 'something' that is not observable and can not be experienced in any way. Note that I did not say either this means the 'something' does not 'exist'. I am simply saying, to repeat it, this question is undecidable by construction.

Best,

B.

Bee said...

Hi Phil,

No interesting story I am afraid. I took the book to the beach, read the first pages, left it in the holy trunk of my car, rainy day, wet street. Next time I saw the book it had considerably inflated.

It's the hardcover version.

Actually Smolin should take this as a good sign, for as often time happens when one is subjected to such ridicule it means others find you are getting to close to exposing their own fallacies.

Depends on what you mean with good sign. I find it a bad sign he did expose various fallacies, but was not taken seriously. I'd call that denial.

He thinks they should be protected and I agree and yet fail to see how this could be done practically in our existing climate.

Well, I'd have a lot to say about this as it's one of the topics I have been concerned with for a long while, but this comment section isn't quite the right place. It will certainly come up again and again on this blog. Lee's book is somewhat disappointingly brief and vague on the practical questions (maybe I could say for me it's too philosophical). On the other hand he managed to draw attention to the issue, which is a starting point.

Best,

B.

Anonymous said...

Phil:

Actually, the example you give illustrates my point very well, in that it shows how incorrect views about what is objective and what is subjective have lead physics astray for nearly a century.

It seems fairly obvious in retrospect that the disagreements between Einstein and Schrödinger on the one side, versus Born and Heisenberg, on the other, were largely due to the failure, on both sides, to clearly distinguish the subjective from the objective content of quantum mechanics.

In particular, probabilities are subjective: they describes the state of knowledge of the observer. By attempting to treat probabilities as objective properties of the particles themselves, both sides of the argument ran into self-contradiction.

On the other hand, by treating the wave function as a probability density of stochastic particle trajectories, all the apparent paradoxes disappear. It is then no surprise that a Wick rotation transforms the Schrödinger equation into the Fokker-Planck equation, whereby quantum mechanics is seen to be just statistical mechanics treated by the calculational method of analytical continuation in time.

Already in statistical mechanics, one sees the phenomenon of correlation distances which diverge to infinity in consequence of purely local interactions. This apparent violation of causality mirrors problems in quantum mechanics such as those pointed out by John Bell or Einstein, Podolsky and Rosen. But the paradox disappears as soon as we realize that it arises from our treatment of stochastic dynamics by analysis of the time-evolution of probability distributions: the non-locality is in the description, not in the system!

Of course, this argument will make no sense to those who hold that it is meaningless to distinguish between the subjective and the objective aspects of reality.

However, if you are interested in seeing experimental confirmation of my argument, I highly recommend the work of Yves Couder and Emmanuel Fort of the Université Paris Diderot, who observed interference fringes resulting from the stochastic trajectories of oil droplets having a diameter of about 1mm! Clearly, the wave-particle duality has nothing to do with some mysterious “spooky action at a distance” that arises only in quantum mechanics. It arises already in purely classical stochastic dynamics.

Couder, Y, & Fort, E, 2006: Single-particle diffraction and interference at a macroscopic scale. Phys. Rev. Lett. 97, 154101.

Andrew Thomas said...

Heck, Anonymous, can you translate that into English! (Only joking!)

I didn't spend too much time reading all that (!) but are you saying that during the measurement process, all that happens is the experimenter obtains more knowledge of the system (I think that was Neils Bohr's initial idea). If so, then surely Bell's inequality experiment has shown that that simply is not the case: something genuinely weirder than that is going on - "spooky action at a distance" is a genuine effect (see my quantum entanglement page).
Bell's inequality doesn't just say something vague about probabilities like your suggested solution - it says very specifically "If this particle is spin up, then this particle 100,000 miles away will be found to be spin down". Neils Bohr's initial idea just didn't hold up to experiment.

There's more going on during measurement than just the experimenter gaining more knowledge about the system. Bell's inequality showed "spooky action at a distance".

"Of course, this argument will make no sense to those who hold that it is meaningless to distinguish between the subjective and the objective aspects of reality." I can see where you're coming from, but you just can't explain away Bell's inequality by your reasoning. Quantum mechanics is weirder than you suggest.

Anonymous said...

Bee:

One cannot make sense of the shadows on the cave wall unless one interprets them as shadows of something real which exists outside the cave, distorted to some degree by the shape of the cave wall.

Every time this interpretation leads to deeper understanding of the properties of the shadows, this constitutes evidence supporting the existence of the external something. While we can never prove -- deductively -- that the external something exists, the accumulation over time of such supporting evidence has by now made the existence of the external something overwhelmingly likely.

Bee, this is the clearest statement I can make of what I am trying to say to you; this is the argument, which you still have not addressed.

By the way, you write “One could thus as well say the something 'is' the information. Just that you don't like this.” To see why the issue goes far beyond personal taste, see my reply to Phil in my previous post.

Anonymous said...

andrew:

I don’t want to hijack this thread and turn it into a quantum mechanics thread. But my point was that the non-locality is not part of the system, it is part of the description. Therefore the collapse of the wave function in quantum mechanics (independent of the separation of the entangled particles) and the divergence (to infinity) of correlation distances in classical statistical mechanics are two sides of the same coin. It is not an intrinsically quantum effect. Statistical distributions are non-local. There is nothing spooky about it. But statistical distributions are not systems; they are descriptions of systems. Thus it is crucial to distinguish the subjective from the objective, otherwise one runs into apparent paradoxes, which are actually not paradoxes at all.

Phil Warnell said...

Hi Anonymous,

“Actually, the example you give illustrates my point very well, in that it shows how incorrect views about what is objective and what is subjective have lead physics astray for nearly a century.”

None of what I referred to or said had to do with the subjective as opposed to the objective. It simply has to do with what is to be considered as admissible in a logical argument. Appealing to reality when it itself is what is being attempted to be described is not admissible in such circumstances.

As for the rest of what you have to say, from what I can briefly gather it is nothing new, for this is also what can be expected when QM is looked at from Bohm’s perspective (which I already have a affinity for). However, this post has to do with Bee’s contention which has no relevance to these matters strictly speaking.


Best,


Phil

Andrew Thomas said...

Hi Anonymous, yes, I see where you're coming from with objective and subjective reality, and it is explained very well in this extract from Quantum Enigma. But like the book says, classical probability is subjective whereas quantum probability is objective. I agree with that.

Bee said...

Hi Anonymous,

One cannot make sense of the shadows on the cave wall unless one interprets them as shadows of something real which exists outside the cave, distorted to some degree by the shape of the cave wall.

That something has to make sense to somebody is another ill-defined requirement (not to mention that it is strongly affected by social and cultural influences). Do you really want to try defining what it means 'to make sense' to a human being and explain why it is relevant?

You can call it an interpretation, or a hypothesis, a theory or whatever, I don't mind. It is certainly a procedure we do all the time.

Every time this interpretation leads to deeper understanding of the properties of the shadows, this constitutes evidence supporting the existence of the external something. While we can never prove -- deductively -- that the external something exists, the accumulation over time of such supporting evidence has by now made the existence of the external something overwhelmingly likely.

Bee, this is the clearest statement I can make of what I am trying to say to you; this is the argument, which you still have not addressed.


I have already addressed this 'argument' twice before. To repeat it one more time:

First it is not clear here what you mean with 'external something' as it is apparently not the same context in which you previously attempted to define 'external reality'. I thus take it to be the analogue to Plato's objects casting the shadows?

I doesn't seem to be of much use, but I will try again to explain why then this 'argument' of yours is none: you do never have any supporting evidence for the existence of the external something. Your claim that it is 'overwhelmingly likely' has no foundation whatsoever. How can I possibly be clearer? You can collect evidence that a theory describes your observations well. That's what we do all the time. But you can never collect evidence (observation) for the 'existence' of 'something' that is not observable.

Best,

B.

Anonymous said...

andrew:

You write, “classical probability is subjective whereas quantum probability is objective.” This is exactly the error which I am warning against. All probabilities are subjective, in the Bayesian sense, independent of the field of application. Calculating with probabilities is a way of extending the rules of logic to situations in which information is incomplete or uncertain. Thus a probability is not a property of a particle; it is a tool we use in reasoning about the properties of particles.

Anonymous said...

Phil:

If you decree that only deductive syllogism is admissible, then you limit yourself, by decree, to being unable to address the existence of external reality. But if you expand your horizons to include inductive inference, then the weight of the evidence supporting the existence of external reality grows with every observation you make -- indeed, with every sensory impression you experience. Then you need only pick an epsilon and declare yourself convinced when the probability of the existence of external reality approaches unity to within epsilon.

But, if you decree that zero is the only value of epsilon acceptable to you, then you unduly limit your reasoning. And yes, in that case you cannot say anything about external reality -- but only because you have censored yourself by choosing epsilon injudiciously.

Anonymous said...

Bee:

Something “makes sense” when it is a minimal consistent interpretation of known facts, constructed through valid reasoning. This is completely independent of culture or preference. However, it has become abundantly clear that you and I cannot agree on what the known facts are, or what constitutes valid reasoning.

I say that the shadows on the cave wall contain evidence for the existence of an external something, and you reply that I never have any evidence for the existence of an external something.

I say the shadows on the cave wall constitute observations of the external something, and you repeat the dogma that the external something is unobservable.

This reminds me of Monty Python’s “Argument Department” skit. No it doesn’t. Yes it does. No it doesn’t. Yes it does............

Phil Warnell said...

Hi Anonymous,

“Calculating with probabilities is a way of extending the rules of logic to situations in which information is incomplete or uncertain. Thus a probability is not a property of a particle; it is a tool we use in reasoning about the properties of particles.”


In the Bohmian perspective that would read:


Calculating with probabilities is a way of utilizing the rules of logic to situations where although all particle actions are determinate are however rendered as to be in total unknowable by the observer. Thus a probability is not a property of a particle; yet rather it represents the maximum knowledge attainable by the observer as to how the particle’s action has been or will be influenced by the wave.


Here the particle is the shadow and the wave the light, which although considered to be real (beable) can only be inferred to exist by the action of the particle. Now this also has a part that cannot be confirmed by direct observation and yet can be inferred by observation consistent with both what you refer to as deductive inference and inductive inference. You on the other hand are content with having only one and yet would deny the validity in having only the other or both.


By the way, I do not agree with your terms or classifications of logic, as they should be only classified as deductive and inductive reasoning. To say deductive inference is a nonsensical term for it means deductive deduction, while inductive inference means inductive deduction which is where observation is substituted for premise. This renders the method vulnerable not only as to the quantity of observations made, yet also the quality of them and relies further on the applicability/viability (connective strength) of the statement formed. Deduction relies only on the soundness of the premise, which is to be a self evident truth or one that has previously been deduced from one. In Bee’s proposition (as I see it) her only proposed premise is her own existence, while it perhaps does not consider other(s) does not deny them. How then can you deny this as being reasonable?


Best,



Phil

Bee said...

Hi Anonymous,

Well, thanks for the clarification, I can make sense of 'consistent' :-)

However, I am afraid you really don't understand what I am saying. You are confusing two different things: I guess what you have in mind is the usual 'scientific method' as it is commonly explained. One has an hypothesis, say, if you let go of an apple it always falls to the ground. Strictly speaking, you'll never be able to show this to hold for all apples and always, but if you've dropped enough apples you can say you have gathered a lot of data that supports your theory, so it seems to be a good description of our observations, and is useful to make predictions etc. That's what I call scientific.

In contrast to this, you are now considering a hypothesis that says an apple is more than what we can observe of it. There is no observation that can ever support this hypothesis, because it is by construction impossible. That's why I call it unscientific. I say it is impossible not because you can never prove it to hold always and everywhere, but because you can not collect any evidence in even a single experiment. You can drop an apple and it falls to the ground. You can never make an experiment confirming that an apple is more than what you observe of it. If you find it handy, you can think of the apple as being 'more' than you observe of it, or it being a 'something' with unobservable (and undefined) additional qualities that you can call 'real existence', but this is a believe and can never be more than a believe. If you like that better: The idea there be 'external reality' if it has unobservable qualities is not even wrong - there is no way to ever disprove it. As I must have said repeatedly, I certainly acknowledge it is a widely used concept, but what I am apparently rather unsuccesfully trying to communicate is that the question whether there is 'something' more than our observations falls into the realm of philosophy.

Best,

B.

Andrew Thomas said...

Hi Anonymous, you say "Calculating with probabilities is a way of extending the rules of logic to situations in which information is incomplete or uncertain. Thus a probability is not a property of a particle; it is a tool we use in reasoning about the properties of particles."

Though, of course, with quantum mechanics it's not the case that our information is incomplete or uncertain: all we can ever know - our maximum knowledge - is the wavefunction. That's why I suggested that the probability is objective - it's not just an "increase of subjective knowledge of the observer".

And it's important to realise that the wavefunction is more than just a probability wave as you can get destructive interference patterns from a wavefunction, and probabilities can never be negative (Born's idea of a "probability wave" is really not accurate). So if there is a quantum reality, it looks like it is the wavefunction itself (as Penrose suggested).

It sounds like you're suggesting some form of hidden variables theory: "by treating the wave function as a probability density of stochastic particle trajectories, all the apparent paradoxes disappear". Is that right? I don't really get what you're saying about all that "stochastic trajectories" stuff, but it sounds like hidden variables - some objective reality which we cannot access?

This is getting very off-topic, so I think I'm outta this thread from now on.

Plato said...

Bee:You can never make an experiment confirming that an apple is more than what you observe of it. If you find it handy, you can think of the apple as being 'more' than you observe of it, or it being a 'something' with unobservable (and undefined) additional qualities that you can call 'real existence', but this is a believe and can never be more than a believe.

While using the Plane of Simultaneity for consideration, it is only with the context of a photon's interpretation that we may say there is a decomposable limit to the interpretation. Just trying to use the "frame of reference" given above.

By defining the decomposable limits of this frame of reference there is no other interpretation then that would suffice, if we are to say that such galactic communications could ever exist in the way our knowledge of science has taken us closer to that indecomposable limit of the vlaues in the originations of the beginnings of our universe?

I would then site the "calorimetric use and measure "in the interpretations of such collisions which map a greater depth of meaning, more then, and higher then, the one we see in glast use?

I have always appreciated Lee Smolin's stance even though we understood the model form, based in the valley, has been pushed beyond the reference he made in his book.

The relativistic interpretation has to be a result, and my definition this had to have a indecomposable limit, and thus, a model chosen can do this?

Anonymous said...

Phil:

Yes, David Bohm’s elaboration of de Broglie’s pilot wave theory has much to commend it. However, nature of the wave function may be slightly less unknowable than Bohm believes. See, for example, the Clifford algebraic formulation of the relativistic Dirac equation by David Hestenes. This approach offers a tempting geometric interpretation of the spin of a fermion and a geometric origin of complex probability amplitudes.

Hestenes, D, 1990: The Zitterbewegung Interpretation of Quantum Mechanics. Found. Phys. 20(10):1213-1232.

Regarding induction versus deduction, it is certainly not the case that I am “content with having only one and yet would deny the validity in having only the other or both.” Quite the contrary. Where self-evident truths or complete, perfectly accurate information are available, deduction is, of course the method of choice. However, when reasoning about the existence of an objective reality external to ourselves, this is rarely, if ever, the case.

My point is that one is not rendered helpless in this situation; one can proceed by induction. And yes, in this case the inference is vulnerable to the quantity and quality of the available observations, but at least one is not forced to throw up ones hands and give up entirely.

However, there is more to it than simply replacing premises with observations. One must also replace the operation of logical deduction with the operation of updating a conditional probability using Bayes’ Theorem. This is the process I refer to as “inductive inference.” It is a method of drawing uncertain conclusions based on uncertain premises, complete with the principled propagation of uncertainties from the premises to the conclusions. This process reduces to logical deduction in the limit, were information is complete and certain.

I agree with you, by the way, that the nomenclature “deductive inference” as opposed to “inductive inference” is problematic, because many people automatically equate inference with deduction. However, inference is defined as the process of arriving at a conclusion from the given information, which includes both induction and its limiting case, deduction.

Anonymous said...

Bee:

I find your last post very reassuring. Perhaps we are not that far apart after all. Yes, your description of the scientific method matches my view of it. And yes, this method is central to my argument. Where we differ is in our opinions of whether this method can be applied to the question of the objective existence of the apple. I say it can, you say it can’t.

You think that to hypothesize that the apple is real is to hypothesize that the apple is more than what we can observe of it. I say that the things we can observe about the apple are sufficient for the purpose of establishing that apples are real, at least to the same degree that we can establish that apples fall to the ground when dropped, as in your example.

Indeed, the very fact that I can make observations about the apple is already evidence supporting the hypothesis that the apple is real. But before I go on, I would like to verify something: surely you will agree that the apple is either real or it is the figment of someone’s imagination, and that there is no third possibility?

Anonymous said...

andrew:

I agree with you: let’s not hijack this thread. So I’ll just refer you back to the paper I cited by Couder and Fort, describing an experiment which demonstrates interference fringes in a classical experiment. This proves that negative probabilities are not needed for destructive interference. I think this experiment is enormously significant because, you see, a probability distribution over a tangle of possible trajectories is not a local hidden-variables theory, so it doesn’t contradict Bell’s Theorem. But it arises out of purely local interactions, so it satisfies Lorentz invariance, too. Poof! No more spooky action at a distance! Quantum mechanics doesn’t need it.

pollywog said...

surely you will agree that the apple is either real or it is the figment of someone’s imagination, and that there is no third possibility?

red pill or blue pill ?

Bee said...

Hi Pollywog,

Yeah, indeed, the original version of my apple-argument was about spoons, but then I was afraid the discussion would only degenerate even more. It's kind of obvious to drift into this direction, but please, lets not turn this into a discussion about virtual reality. Best,

B.

Bee said...

Hi Anonymous,

You think that to hypothesize that the apple is real is to hypothesize that the apple is more than what we can observe of it.

No, I don't think that. I have re-re-repeatedly tried to tell you that I do not even know what you mean with 'real' and what I wrote above was based on my interpretation of what I guess you might have meant with it. So, I ask you again: please explain what you mean with 'real', because otherwise any hypothesis about what you can conclude about it is completely meaningless.

I say that the things we can observe about the apple are sufficient for the purpose of establishing that apples are real, at least to the same degree that we can establish that apples fall to the ground when dropped, as in your example.

If you can have an observations that something is 'real' then 'real' must be an observable fact and something being 'real' can never mean more than something contained in the totality of observations that you have. That's what I already said repeatedly above.

Indeed, the very fact that I can make observations about the apple is already evidence supporting the hypothesis that the apple is real.

Please explain what you mean with 'real' and what is the observation that shows an apple has this property.

But before I go on, I would like to verify something: surely you will agree that the apple is either real or it is the figment of someone’s imagination, and that there is no third possibility?

I don't know what reality is and I have no basis on which to answer this question.

Neither do I know what you mean with 'imagination'. It is commonly used to mean 'something that is not real'. Even without knowing what 'reality' is, this would imply that something which is real can not be imagination or the other way round. So what is your question then?

I am not picking around on these concepts because I want to appear as a smartass but to make clear that your questions are ill-defined and your conclusions thus have no basis.

Best,

B.

Anonymous said...

Bee:

Now you contradict yourself -- just when I thought there was hope.

First, you write “you are now considering a hypothesis that says an apple is more than what we can observe of it.” And you elaborate that this hypothesis says that the apple is “a 'something' with unobservable (and undefined) additional qualities that you can call 'real existence'.”

In the course of answering you, I reiterate your statement with the words “You think that to hypothesize that the apple is real is to hypothesize that the apple is more than what we can observe of it.”

And you reply by saying “No, I don't think that.” So now you can go on to make any claim you want, because anything is derivable from a contradiction.

In any case, I made it very clear in my last post that being real has nothing to do with having “unobservable (and undefined) additional qualities” beyond what we can observe. But you evade that point by repeating your mantra, “I do not even know what you mean with 'real'.”

What is real is that which has the properties we observe, and which has the properties it has, independent of whether we observe them or not. What is real is therefore that which is subject to the observations of more than one person, and causes those observations to be consistent to within experimental error, even among people who do not exchange information.

This is very clear and very well defined. But I don’t think you will ever admit it. I think you will continue to evade the issue by pretending there is nothing in the previous paragraph that is sufficiently well-defined to be understood. Otherwise you would have to stop claiming that my conclusions have no basis.

Andrew Thomas said...
This comment has been removed by the author.
Andrew Thomas said...

Anonymous, I think you're slightly misunderstanding Bee's point. Let me have a go.

You listed **properties** which a "real" object should have:

1)It has properties we observe, independent of whether we observe them or not.

2) That which is subject to the observations of more than one person.

This is basically the list of properties which Einstein suggested in EPR - fair enough. But I have always found it slightly unsatisfactory. You see, this is really just a test for the presence (or absence) of reality - it does not answer the question "What is a real object?" Einstein's definition was not really a definition of the material of physical reality at all - it was just a test for the presence of a physically real object.

You see, listing **properties** a real object should have is not the same as saying "What is a real object?" (which I think is the point Bee is making). It's much harder to answer the question "What is a real object?"

For example, I could say a dog should have:

1) Four legs.
2) Tail.
3) Fur.

But listing those properties and saying "a dog should have these properties" does not answer the question "What is a dog?". Likewise, your list of properties does not answer the question: "What is a real object?" So when you say "The apple is real", I think you're actually saying "The apple has properties which we would expect a real object to have", but that is actually subtlety different from saying "The apple is real" because in order to say that latter statement you would have to say what a real object actually **is**. And I think that's the point Bee was making.

It's a major, major, jump to go from "The apple has properties which we would expect a real object to have" to say "The apple is real". At least in my book. There is a subtle difference. I'm not even sure it's possible to make the jump. In order to say "The apple is real" you would, indeed have to define reality (Bee's point), and I have never found a definition of "What is reality?" (like I say, Einstein's list of properties really doesn't cut it for me).

It's very difficult indeed to answer the question "What is a real object", basically because we define real objects in terms of other real objects: "I know the apple is real because I can hold it in my hand", for example. The definition becomes circular.

Phil Warnell said...

Hi Andrew,

“But listing those properties and saying "a dog should have these properties" does not answer the question "What is a dog?".”

Correct, as I stated to Anonymous earlier one cannot appeal to reality when what is being described and decided on being reality. The paragraph in EPR that synopsizes all this is as follows:

"One could object to this conclusion on the grounds that the criterion of reality is not sufficient restrictive. Indeed, one would not arrive at our conclusion if one insisted that two or more physical qualities can be regarded as simultaneous elements of reality only when they can be simultaneously measured or predicted. On this point of view, since either one or the other, but not both simultaneously, of the quantities P and Q can be predicted, they are not simultaneously real. This makes the reality of P and Q depend upon the process of measurement carried out in the first system, which do not disturb the second system in any way. No reasonable definition of reality could be expected to permit this."

All the business presented earlier in the paper about "defining reality" is a red herring, as it *is not* a "definition of reality", yet simply a fair condition to consider something as an "element of reality" and serves only to distract one from the key (obscured) issue and that in this case was to point out that QM was non local. The paper does serve to perhaps convince one of this point, yet fails to legitimately rule it out as being reasonable, as it appeals to reality which is logically inconsistent in such instances. To parallel with Anonymous’s contention is to point out that the methodology of reasoning used in such circumstances will not alter this as being a legitimate position in any way.

Best,

Phil

Andrew Thomas said...

I'm sure Anonymous won't like all this!!

I suppose the obvious answer is to say "If it barks like a dog, it's a dog". Well, it's not really - it's "something that barks like dog".

I suppose if we ever could obtain a true definition of "what is real" and "what is reality" then we could indeed distinguish between all this simulated/virtual reality, Matrix stuff, and the real world. Because we could tell what "real" is, what is its material compostion. But it's precisely because we do not have that elusive definition of "real", and are forced to rely on unsatisfactory definitions which rely so much on our senses ("if it barks like a dog ..") and the EPR "definition" which means we will NEVER be able to distinguish between real and simulated reality.

I'm sure Anonymous will come back with all guns blazing so I'm off ...

Phil Warnell said...

Hi Andrew,

Yes it would be nice to have such a definition of what reality is and yet we don’t. However, in defense of Einstein I don’t think he considered he knew either as he never put it this way before or since. His main focus rested with if QM served to be a reasonable representation of it and I “believe” as he it isn’t. Also, as time progressed he was not so concerned “if” something should be considered real yet rather “when” it should be and admitted as much that it all boiled down to belief when in protest to his later to become biographer, Abraham Paris, he said in complaint in asking him (I paraphrase) “whether I really believed that the moon exists only when I look at it?".

It is interesting to note that even though he may also hold the same objection for Bee’s proposition, he would have to likewise forced to realize that he could not prove to deny it.

Best,

Phil

Anonymous said...

andrew:

Yes, exactly. A real object is one the passes the test for the presence or absence of a real object. It is pointless to look deeper than that. There is no mysterious quintessence called reality. Nor can you axiomatize reality. Any attempt to do so would necessarily be incomplete or inconsistent. We can only base our inferences on incomplete and uncertain evidence. So we have no choice but to reason about it inductively.

This may feel unsatisfying, to some extent, but to claim that we therefore can’t say anything at all about reality is an overreaction.

Andrew Thomas said...

Good answer.

Bee said...

Hi Anonymous,

You think I contradict myself because you omitted to notice what I was replying to. In the latter case you asked me what 'I think'. In the apple-example I was trying to draw conclusion about what you were saying.

Let me try to repeat this exchange. I ask you to define what you mean with 'external reality'. You define an object is externally real if observations on it are observer independently repeatable. (I could go and roast you on how you make sure they are independent, but that will only make things more complicated). I say, fine, so now that you've defined it, what's the problem. Then you go on and talk about 'somethings' because, so your argument, observations have to be 'about' something.

I say, well, you can have that interpretation if you want to, but whatever you do, you will never have more information about your 'something' than the sum of all observations on it. You claim yes you can collect evidence that an object is 'real' because you have made all these measurements. Now I am confused because this is just how you defined 'reality' so what is there to conclude? I have no clue what you are trying to say. I therefore assume you have now attached a different meaning to reality, and I explicitly mention it that I have made this assumption.

You say

“You think that to hypothesize that the apple is real is to hypothesize that the apple is more than what we can observe of it.”

And you reply by saying “No, I don't think that.”


I say, no, I don't think that because the answer to this question depends on what you mean with 'real'. It is not a 'mantra', I just think you've changed your definition somewhere, and I am repeatedly asking for it to make sure we are arguing about the same definition.

You asked here what 'I think' and I mentioned previously that I see no point in making a distinction between a real object and the sum of all observations of it, and if I'd use this definition then the answer to your question is clearly 'no'. In contrast to this, my apple-story was trying to grasp your sense of what 'reality' is.

In fact, I think Andrew has already explained what the difference is between how you first defined 'real' and then used it later.

I made it very clear in my last post that being real has nothing to do with having “unobservable (and undefined) additional qualities” beyond what we can observe.


Good.

But you evade that point by repeating your mantra, “I do not even know what you mean with 'real'.”

I just ask you to recall your definition.

What is real is that which has the properties we observe, and which has the properties it has, independent of whether we observe them or not.

You just said that being real has nothing to do with having unobservable qualities and now you say what is real has properties when we don't observe them. Don't you see that this doesn't make sense?

What is real is therefore that which is subject to the observations of more than one person, and causes those observations to be consistent to within experimental error, even among people who do not exchange information.

This is very clear and very well defined. But I don’t think you will ever admit it. I think you will continue to evade the issue by pretending there is nothing in the previous paragraph that is sufficiently well-defined to be understood. Otherwise you would have to stop claiming that my conclusions have no basis.


In the first paragraph you have re-introduced the real 'something' as 'what' causes observations to be consistent etc. To repeat what I said before, you can introduce such a concept and call it a 'real something' but you will never be able to find a single observation that confirms the 'real something' is more than the observations we have about it. Luckily, you previously said being real has nothing to do with having “unobservable (and undefined) additional qualities” so then what is your problem with me saying the only thing we ever have are observations?

A real object is one the passes the test for the presence or absence of a real object. It is pointless to look deeper than that.

If that means repeatability of observations is the only thing we can know, the only thing we need to make science, but also the only thing we can use to explain what we mean with 'reality', that's what I was saying from the beginning on, congratulations.

Best,

B.

Anonymous said...

Bee:

There is a huge difference between “unobservable” and “unobserved.” You write

“You just said that being real has nothing to do with having unobservable qualities and now you say what is real has properties when we don't observe them. Don't you see that this doesn't make sense?”

Bee, it makes perfect sense unless you confuse “don't observe” with “can't observe.”

If you stop reading “unobservable” every time I write “unobserved,” then I think our communication can proceed much more smoothly! Of course I agree that it is completely meaningless to ascribe unobservable properties to anything. So whenever you think I am doing that, please stop and double-check whether I have written “unobservable” or “unobserved.”

You say that you suspect I’ve change my definition of reality. Well, let’s see...

Initially, I loosely equated the objective reality of the universe to the idea that it

“needs no help from anyone to be what it is.”

Most recently, I said,

“What is real is that which has the properties we observe, and which has the properties it has, independent of whether we observe them or not. What is real is therefore that which is subject to the observations of more than one person, and causes those observations to be consistent to within experimental error, even among people who do not exchange information.”

So you see I haven’t changed my definition. Only added detail.

You ask, “what is your problem with me saying the only thing we ever have are observations?” Bee, I have no problem with it. On more than one occasion, I have explicitly agreed with you that all we ever have are observations.

And I also agree with your statement that “you will never have more information about your 'something' than the sum of all observations on it.” This is precisely because all we ever have are observations. That is, we can have direct access to an observation of something, which is information about that thing, but we can never have direct access to the thing which is observed, which is the real thing referred to by the information.

Now, you write, “you can introduce such a concept and call it a 'real something' but you will never be able to find a single observation that confirms the 'real something' is more than the observations we have about it.”

Again, I agree. There is no such observation. However, the concept does not depend on the existence of such an observation, and the concept is necessary to avoid inconsistency in our interpretation of the observations that we can make.

If we accept your definition that an object is no more than the sum of all observations on it, then an apple has no mass until I observe it. And it has no volume until you observe it. And now the apple is a different thing when you observe it than when I observe it. For me, it has mass but no volume, but for you, it has volume but no mass. This is absurd. Further, if we compare notes, we can divide the mass I observed by the volume you observed and suddenly, by magic, the apple acquires a density, even though neither of us separately observed it, but only jointly inferred it. So the apple becomes something different yet again, just because we talked about it. This heaps absurdity upon absurdity.

The simplest hypothesis which resolves all this absurdity is that the apple is a real object, meaning an object which has the properties it has, independent of whether we observe them or not. Then we can conclude that the apple had both mass and volume all along, even though I did not observe the one and you did not observe the latter. And we can conclude that the apple had a density all along, even though it was not directly observed at all.

Thus, the hypothesis that a real object is one which has the properties it has, independent of whether we observe them or not, is inescapable... unless you are content to believe in magic.

Bee said...

Hi Anonymous,

I've spend a lot of time trying to find out what it is that you apparently don't like about something I said, but whenever I try to pin it down it seems you agree with what I say. I don't know what this is good for. Maybe we just agree anyway.

If we accept your definition that an object is no more than the sum of all observations on it, then an apple has no mass until I observe it [...] This is absurd.

I said "if I would use this definition, then..." to explain why the reply to your question is definition dependent. If it is a definition there's nothing more to say about it than it is a definition. You probably find it 'absurd' because it does not agree with what you think a good definition would be that would appripriately capture your idea of what an 'object' is. Besides, I did not say the sum of observations 'a person has made at a given time' or something of that kind, which is actually what you are later calling absurd (I already commented on the problem that you will never in fact know what you call 'somebody else' is actually independent of what you call 'yourself' but anyway). So again, I don't know what you are disagreeing on.

Best,

B.

Anonymous said...

Bee:

Yes, it’s strange.

We seem to agree on all the detailed issues, when we step up and examine them at close range. But then I step back and conclude from those details that objective reality is a meaningful and necessary concept in physics, while you step back and conclude from those same details that objective reality is a meaningless and unnecessary concept in physics.

A great deal of effort has been expended by each of us to understand the other’s point of view and explain our own, but the same pattern repeats: zoom in and agree, zoom out and disagree.

It is indeed strange.

George Spencer Brown remarked in the introduction to his Laws of Form that the subject matter is difficult to discuss, because the ideas are so fundamental that every word we use to express them says too much. Perhaps something like that is going on here. We choose a word because its meaning covers what we are trying to say, but we are stuck with the fact that its meaning also overlaps onto things that we are not trying to say.

Still, it’s strange.

Phil Warnell said...

Hi Anonymous,

“Nor can you axiomatize reality.”

You continue to make statements that often sound reasonable yet are actually logically void. To proclaim that reality cannot be axiomized is a belief, as it is not supported by proof. Likewise, one cannot appeal to reality when it is what is being accessed, which also amounts to nothing more then belief. I would never deny anyone their belief’s, however I would insist it not be allowed to be passed off as logic as it relates to reason. Having reason and being reasonable should never be confused as being one and the same. What you say amounts to nothing more then what Francais Bacon said in the conclusion of his “Novum Organum (New Instrument)” which was:

“To God, truly, the Giver and Architect of Forms, and it may be to the angels and higher intelligences, it belongs to have an affirmative knowledge of forms immediately, and from the first contemplation. But this assuredly is more than man can do, to whom it is granted only to proceed at first by negatives, and at last to end in affirmatives after exclusion has been exhausted.”

This also appears to be a true and reasonable statement and yet does not serve to act as proof; nice rhetoric perhaps, yet proof, certainly not.

Now Descartes had another way to look at this when in his “Discourse on The Method: of Rightly Conducting The Reason, and Seeking Truth in the Sciences” he stated the following:

“The long chains of simple and easy reasonings by means of which geometers are accustomed to reach the conclusions of their most difficult demonstrations, had led me to imagine that all things, to the knowledge of which man is competent, are mutually connected in the same way, and that there is nothing so far removed from us as to be beyond our reach, or so hidden that we cannot discover it, provided only we abstain from accepting the false for the true, and always preserve in our thoughts the order necessary for the deduction of one truth from another.”

I would say that what Descartes states also sounds reasonable and yet without the premise being irreproachable also falls short. I myself favour Descartes vision and yet would both admit and insist that until the ultimate premise is discovered this also amounts to be merely nothing more then nice sounding rhetoric.

Therefore, it must first be understood that despite what both Bacon and Descartes said and believed to be true, that when examined in the face of reason, as it relates to infallible logical proof falls short. That is Descartes’ fails when the premise is threatened and Bacon’s fails when the observations change or are unknown. As far as I’m aware both in terms of science are subjects that remain in dispute and although one may find this at times frustrating, also serves and has proven to be its greatest strength. You therefore may claim that this to be unsatisfactory, however this does not have it to be reason necessitated by logic.

Just as a side yet related remark which is despite however apposed Descartes and Bacon might have seemed as what should be considered the correct route to find truth within the method we call science they both agreed in one aspect which Bacon also expressed in “Novum Organum as follows:

“the mathematical postulate that if two things are equal to the same thing they are equal to one another is conformable with the rule of the syllogism in logic which unites propositions agreeing in a middle term.”

This of course is the equation on which much of science depends and draws its greatest strength.

Best,

Phil

Plato said...

Phil quotesthe mathematical postulate that if two things are equal to the same thing they are equal to one another is conformable with the rule of the syllogism in logic which unites propositions agreeing in a middle term.

I just seen your posting Phil and concur with it's elements

I am not totally satisfied that either party has really explained what "infinite regress means" while looking to the "decomposable element" with which I hold mathematics, as a necessary understanding, while we look to explain the very principals and nature of this universe, and it's accelerations currently established.See my Post on superfluids

You must understand that in order to progress such an understanding of the "phenomenological order" it is understood then such interpretations settle to what is "self evident."

This is the "Aristotlean Arche" that I am referring too. It is given in relation to a philosophical valuation, not only to the philosophy of science, but of physics, as a basis to further this "Theory of everything."

Such an relation is the definition with which an "decomposable element is found in relation to infinite regress."

Anonymous said...

Phil:

The concept of “infallible logical proof” is a siren song that will lure you onto the rocks when you step outside the Platonic world of perfect points and lines and undertake to reason about the real world. In the real world, as I have already pointed out, self-evident truths and complete, perfectly accurate information are extraordinarily hard to come by. But “infallible logical proof” is completely helpless without them -- you cannot even show, by “infallible logical proof,” that the sun will rise tomorrow.

In the real world, all we have to work with are approximations and hypotheses, the accuracy and completeness of which we can only estimate. We must therefore admit that they are really only beliefs, although we are justified in believing some of them rather strongly. Now, a probability is nothing other than a quantified degree of belief. Therefore, the only choice we have, if we want to reason at all, is to reason using probable inference.

Unfortunately, there is a strong association in the minds of many people between “belief” and “blind faith.” Not only does your post disingenuously exploit this association through innuendo, but your whole argument rests on the implicit assumption that any belief not grounded in “infallible logical proof” must be no better than “blind faith.” However, this is utter nonsense.

Bayesian statistical inference is a principled way of revising the strengths of our existing beliefs when we acquire new, uncertain, evidence. In fact, it can be shown that any consistent generalization of the Boolean field of two elements (true and false, represented by 1 and 0) to a continuous measure of belief must satisfy the laws of probability, and that the application of Bayes’ Theorem to such probabilities the only consistent way of reasoning based on uncertain and incomplete information. Of course, when all information is complete and certain, all probabilities reduce to 0 or 1 and Bayes’ Theorem reduces to modus ponens.

I have outlined all this in several previous posts, but you still insist on bringing a knife to a gunfight.

Phil Warnell said...

Hi Anonymous,

“I have outlined all this in several previous posts, but you still insist on bringing a knife to a gunfight.”


I can see you are fond of this analogy as you’ve used it several times. In regards to addressing your rebuttal it appears to be most likely fruitless, since you never address what’s being focused on and further misrepresent and misinterpret as to what was said. So just for the record, it cannot be considered logic to call on reality to decide on reality as to insist what it must be. Also, it cannot be considered as logic to proclaim that you can’t axiomize reality without submitting proof.

As for your admitted beliefs I will repeat again that I hold no disrespect for anyone based on having them. In fact I would insist that a lot of good science is discovered partly resultant of people holding to their beliefs or convictions if you prefer.

The central point which you fail to or perhaps refuse to acknowledge is that when one uses such as the bases to dismiss another’s hypothesis, this cannot be considered either to be logic or science.

Oh by the way, I would also have you know that accusations such as “disingenuously exploit this association through innuendo” I take very seriously, particularly when they are completely groundless. What I will insist as being evident for me is that you consider your own “judgment” to justly serve as replacement for logic and proof.

Regards,

Phil

Anonymous said...

Phil:

You are stirring up a lot of mud to cloud the waters instead of replying to the substance of the posts I addressed to you, which was the argument that inductive inference is much more suitable for reasoning about the real world than deductive inference.

But is seems you are unable to debate this topic civilly, so this exchange is rapidly degenerating into a personal quarrel, in which I will not participate. You may have the last word if you wish.

I am done with this thread.

Plato said...

Our attempt to justify our beliefs logically by giving reasons results in the "regress of reasons." Since any reason can be further challenged, the regress of reasons threatens to be an infinite regress. However, since this is impossible, there must be reasons for which there do not need to be further reasons: reasons which do not need to be proven. By definition, these are "first principles." The "Problem of First Principles" arises when we ask Why such reasons would not need to be proven. Aristotle's answer was that first principles do not need to be proven because they are self-evident, i.e. they are known to be true simply by understanding them.