Saturday, May 03, 2008

Every Now and Then

This is a continuation of my earlier post 'Interna' with the poll "Does the past and the future exist in the same way as the present?". By now (130 votes) the results are approximately: 30% think it is only the present that exists, 15% think the past and the present exists, 41% share my believe that the past and the future exists in the same way as the present does, and the remaining 14% picked 'Other' [1].

The comment section to the previous thread is interesting as one finds a broad spectrum of opinions there. Just to put some of them on the table, e.g. Wolfgang said in the first comment

    I would think that past and future do not exist the same way, otherwise why would you feel the need to distinguish past and future from the present and why would the question even come up?

And right the next comment by Count Iblis said
    The fact that the "now" is real implies that the past and future must also be real in exactly the same sense as the "now".

Somewhat further down, Quantum Ranger explains
    Well there can be no part of the past wherby any change is occuring, the past is not available for change of any kind, thus is not like the present time or future.

Another interesting point of view is Carl Brannen's who argues that the present and the future exists, but not the past because 'if it exists, why is it not alterable?', and CIP states
    The problem with shuffling the present into consciousness and psychology is that it doesn't solve anything. If consciouness can conjure up the present, how does it do it? With physics or some kind of magic psycho juice?

    And if it's magic psycho juice, what is the physics of that? We can imagine that the division of time into past, present, and future is an illusion, but don't forget that you can't do any physics or even plan your breakfast without it.


So the following is an attempt to clarify why I am 'shuffling the present into consciousness'. I am not saying this is the only viable point of view, it is just a brief writeup of my thoughts on the matter.


Now

To begin with I want to focus the point of discussion. I believe most of us have the feeling that the present moment is somehow different from the past and from the future. And that moment is constantly changing, thus the impression that time 'flows'. Yet, if you look at some law of nature or a theory describing the evolution of a system, there is no such thing as a present moment there. You can have a time in that description, and to every time you have a configuration. But all of these times are equally there or not there, none of these moments is special. So there is nothing in this description that explains our impression of a 'now' being different from the 'then'.

If you don't find that explanation very illuminating, maybe try the introduction to Lee's first 2008 lecture, min 42.14 - 49.00 (PIRSA 08010033), which also makes some references to psychology that I'll come back to later.

A different question is why the past is different from the future, or where the arrow of time comes from. I don't think this question is unrelated to where the 'now' comes from, but I don't want to discuss the arrow of time here. I will just assume that we have one and that information reaches us from the past, but not from the future for some reason. Another different question is what time actually is. For the following I will just take the point of view that time has proved to be a useful concept in our theories.

Needless to say, my believe that the past, present and future exist in the same sense goes back to time being a coordinate in Minkowski-space and not a parameter. Since some people commented on this in the previous post with mentioning the problem of time in General Relativity, let me emphasize I didn't say it follows that nature can't be a succession of present moments for this reason [2]. I'm just saying that very possibly this is the origin of my personal opinion, and I occasionally wonder how far our education influences the opinions we hold on philosophical questions [3].

Then

So what actually is the problem with the now? To me the question seems to be how can it be we experience a 'now' that is different from all other moments without that being an ingredient into the fundamental laws of nature. To me, human beings are some rather complicated systems in a four-dimensional spacetime. In the common picture we have worldlines on which the events in our lives happen. The question then becomes how can it be that in every moment we think this moment is special, but the next moment it's a different moment that is special.

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. Memory that lies further in the past is different than the more recent one, most importantly it comes with some 'time-stamp' (that can be imprecise for the human brain but this isn't the point here). Since we have an arrow of time, we can't have memories of the future.

In every moment that moment itself is the most recent one, it is the newest piece of information in that memory and is thus special. Yet the next moment, it will be that next moment which is special. If you just draw a trajectory of a particle moving on a world line, say some curve x(t) in a space-time plane, you can't find anything like a 'now' because it doesn't have anything like a memory. For this, you'd need an additional quantity. E.g. for every t you don't only have an x(t) but also some kind of memory belonging to that moment t that stores some information about earlier times t', which one could denote as Mt(t') - the arrow of time would enter in some requirement like Mt(t') =0 for t'>t. One can extend such a concept to a space-time slicing instead of a trajectory, where the moment is the tip of the past lightcone, and the memory can contain everything in that past lightcome.

Unfortunately for drawing something like this you'd then need at least four dimensions which doesn't work well with the blogger software. So I'll try to give you an example. Consider the particle on its trajectory does 'collect' bits of information while propagating. From these bits, it forms a string of 0's and 1's which constantly gets longer, while the relevance of these bits becomes smaller the further this information already lies in the past. So you'd have a string of bits with the most recent piece if information always being the most relevant one.

With some pictures, consider you have this series of events (the 'trajectory')


[Picture: Sleepzine]


If you'd add the memory of earlier moments to every picture it would look like this (times runs downwards)




Of course the human brain is more complicated that that. For example, lack of sensory input (like e.g. turning in bed at night) makes it very hard to accurately judge on the passage of time. Thus the impression the night lasts forever, even though the next morning it doesn't seem to occupy much memory (at least that's my experience). But I hope you roughly get the point that every moment can be subjectively special if rated on its quality within the available information in the memory, even though objectively all moments are equally special or non-special.

That is to say, even if the past exists in the same way as the present and the future, we'd still find every moment is unique.

Psychology?

I wouldn't say this explanation falls into the realm of psychology. Rather it's possibly neuroscience or biology. The way our brains store memory is a useful organization of information, that allows us to perform a lot of impressive tasks like e.g. constructing and driving cars, searching for the Theory of Everything, or reading this blog (in this order ;-). I am just skeptic about the argument that because we perceive a 'now' there must be something fundamental about it. Just to make clear, I am also not arguing the opposite has to be the case - in the above I have just explained why I think that human consciousness plays a role for this question.

I certainly don't suggest "some kind of magic psycho juice" as I hope is clear now. I think that it should become possible to examine this scientifically with our increasing knowledge about the way the human brain works.

Which features a system needs to have to perceive such an effect is probably a very tough question. Trees too store memory of the past, but finding out whether they have any experience of a now I guess requires a decent amount of treehugging.

Bottomline

I do not think the fact that we perceive the 'now' as being different from the 'then' is a fundamental property of nature, but rather a consequence of the way our brains store and organize information. We are able to store past experience in a memory, and information is perceived differently depending on how old it is. The present moment plays always an especially important role, but this is a subjective experience. In a nutshell this is why I believe the flow of time is an illusion.

PS: If you think you can change the future, prove it ;-)



[1] I added this option partly because the question isn't exactly well defined. So I guess some of you find the formulation doesn't express your point of view appropriately. If you want to clarify 'Other', just do so in the comment section.
[2] In fact I am fairly sure it does not follow. If there's interest, I can elaborate on this in another post.
[3] I strongly suspect that the outcome of the poll (with the majority favouring the block universe) is not very representative for the opinion of the average person on the street, but that it is dominated by people with an education in physics.


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71 comments:

Qubit said...

Isn’t the arrow of time just a measure of entropy? If you had a perfect mind the arrow of time which most people imagine, would struggle to keep up.
Our entropy of thinking is much lower than the universes entropy, but that does not seem to show up in modern thinking. I Think memories of the future do surface, but it is easier to imagine the far future than our own future.

When I examine my past, I realise that certain related events happened at different times, but equally could have happened in succession; e.g. they seen to have spread out and happen out of sync. Had they have happened in sync and in succession of the connected event I would not be here, I would be dead. Therefore those events could only have happen out of sync. It would appear to me that there is more than one type of time. One type of time seems to have connected loops and one seem to continue to push the connected loops forwards into a future.

Neil' said...

One of the problems is, you're using tense-based language (which assumes time to begin with) to ask, whether the past and future exist in the same sense as the present etc. I would say, the past did exist, the future will exist. We should just accept time and quite trying to compress questions about the reality of past and future into language appropriate to asking about things that do or do not exist "now." I know this "common sense" intuitive perspective is not the most fashionable anymore, but I just don't accept the block universe or any treatment of time which tries to "denature" it or hollow it out into just something about space/s and structures in the end.

Kris Krogh said...

Hi Bee,

From your reply in the preceding discussion:

The question why time has an arrow that points this way and not that way is certainly interesting, but it is a different question to whether it is only the present moment that exists. Not saying these two issues are unrelated though, I just think they have a different origin and entangling them might not be helpful.

Okay, we'll put aside the issue of time's direction. Without mentioning that, Lorentz-Poincaré relativity still has the feature that space and time are kept separate. (Newton's universal time exists there in some preferred reference frame.) Instead of a dimension, time remains a parameter which says this is the present. That's its only job.

Of course I can't give a deeper explanation of time. I can't do any better than Feynman, who used to joke "Time is how long we have to wait." Or "Time is what keeps everything from happening all at once." No matter how far things progress, I think we'll always have to make some fundamental assumptions to do physics.

I share Ilya Prigogine's view. Asked to write something on a wall inscribed by other famous thinkers like Dirac and Bohr, he wrote: "Time precedes existence." (He also felt strongly that time should not be spatialized.)

Comparing the special relativity of Lorentz and Poincaré to Einstein's, John Bell wrote:

The facts of physics do not oblige us to accept one philosophy rather than the other .... Einstein starts from the hypothesis that the laws will look the same to all observers in uniform motion. This permits a very concise and elegant formulation of the theory, as often happens when one big assumption can be made to cover several less big ones.

To "explain" any phenomenon, just add more complexity to space-time and call that fundamental. Introduce any number of dimensions, make it curve, make it drag around, make it loop, make it discrete. As long as you call it a space-time (and not ether), that counts as one assumption.

It's true Lorentz and Poincaré were unable to formulate a viable preferred-frame theory of gravity. But at least one exists now which agrees with all the usual experimental tests of GR. Unlike GR, it is immediately compatible with quantum mechanics, which likewise is based on a time parameter rather than a time dimension.

Best wishes,

Kris

John G said...

The common sense view of time doesn't fit just cause of relativity where your refernce frame can change the order of events. I agree with Bee that you have to look at the worldline and I like the memory part. The only thought I have is how anybody might think a worldline "now" could change depending on whether you are a massive brain or a massless photon. The "now" is kind of where you get a branching choice and how does that work for a photon?

Phil Warnell said...

Hi Bee,

Again an interesting topic and one I admire that your would just come out and reveal to all what you current thinking is, as to the nature of time and what part consciousness plays if any. I also thank you for pointing to this Smolin lecture, which I discover is only an introduction to a whole research intentioned course. To be truthful, after weighing all that was presented in his outline for consideration, it served to have me question more my own position on this rather then strengthen it, which I might add has never been that strong outside your own understanding which I share, that time is a dimension on equal footing as the spacial ones and while indistinguishable in some sense from the other degrees of freedom still somehow unique.

At first I thought I should forgo any attempt to render an opinion, as I have always been humbled by a problem that has confounded all that have approached it seriously. However, in as it is such an open issue and one of great interest and importance that appeals to both my scientific and philosophical curiosity I will just sum up how I look at it all.

To begin (no pun intended), I agree with you that time should be considered real as any dimension would be and yet not necessarily the same. The other dimensions I would agree have an eternalness to them that doesn’t require time as an aspect. However, I contend that time is actually the entity that enables the other degrees of freedom to become dynamic rather then static qualities. Strangely enough I wrote one of my few and far between blog entries about this called “Time, is it an Essence?” back in February of this year, where I make use of a admitted crude analogy to flesh out my thoughts on this further. As you know I don’t promote my blog for even I don’t consider it to be one in the serious sense. I just thought it would serve to shorten my explanation, despite the fact it will probably serve more to expose my ignorance as some would perceive it.

Where we do differ in all this, is that you appear to believe that the now only exists or is distinguishable from the rest of time resultant of our minds recording of it. I would agree with this as far it goes and yet suggest that the recording is extended to what we actually call reality and that the cosmos itself is the record if you will. Where I still struggle, is if the other dimensions are of a fixed although individually varied nature; or are they dynamic in some fashion among themselves as to further complicate the potentials which are realized. Anyway, this is my own humble opinion as it relates to such a serious and perplexing problem. What you now have forced upon me is to follow up on the other Smolin lectures, as to consider all the things I have missed and know nothing of.

Best,

Phil

Serenus Zeitblom said...

Apologies if somebody has already mentioned this, but I think that Bee would find this reference very interesting:

http://arxiv.org/abs/gr-qc/0403001

Hartle was/is/will be one of the most interesting people.

Plato said...

Bee: If you think you can change the future, prove it ;-)

Some questions then come to mind.

If the depictions of the cartoons are worth anything, it is to remind the dreamer is observing and very capable even when it is squeezed for time:)

Anything Ramanujan developed in terms of his mathematics is not true. True or false?

Can't remember which fallacy that question falls under.:)

Quantum physics is an unusual field of science because it enables scientists to make predictions on the basis of probability?

Mathematical models and computer models are frequently used to both describe the behaviour of something, and predict its future behaviour?

Enrique said...

Hi Bee.

A very interesting post. These ideas are bouncing in my mind all the time. I also think that time flow is an ilusion, one of several powerfull illusions of our brain. I think that time flow has the same quality of the "redness" of red and the "coldness" of ice. We describe color by the wavelength of light. The way of our brain to know about that wavelength is that redness experience which cannot be communicated. I'm not saying that qualia do exist. What I say is that our brain handles that color information in such a way that creates this subjective experience. The same happens with sound. Althought soud is fully described physically by the speed, frequency, amplitude and shape of the wave in some media, we cannot figure out how it "sounds" until we acutally listen it. Same goes with temperature or odors. This doesn't mean that the world out there doesn't exist or that only exists in our mind. However all the perceptions that reach our brain have an existence that we consciously accept and I would say that that is the part consciousness plays here. We perceive that time flows and that is our brain's way to know about time.

As to how time is, I'm inclined to say that past, present and future are just useful concepts created by our brain to handle our day to day survival.

But what is the "true" nature of time? I don't know and I don't know if even a theory of everything will have something to say about that. Our theories are our efforts to explain and correlate our observations and because they are our unique way to know about the world out there, maybe we will never get an absolute answer but answer that works.

Nevertheless, let's keep thinking we never know what we may discover!

John Baez said...

After you've settled the question of whether the past and future "exist", maybe you should ask your readers if other places are really "here" - you know, just like it is here.

And then: are other people also "me" just like I am?

Some of our problems with these issues are grammatical in nature.

On a different note:

The main problem with the simple-minded "block universe" is that it's a classical picture. In reality, we have to take the uncertainty principle into account. So, maximal knowledge about a specified set of aspects of the universe now precludes maximal knowledge of the same aspects of any other "now".

For example: according to Schrodinger's equation, the position of an electron now does not commute with its position at any other time. So, knowing its position now makes the whole question of its position in the past or future somewhat moot.

In other words: from the viewpoint of our "now", a bunch of information about the past is really gone - so completely gone that it doesn't even make sense in principle to ask exactly what happened. Same with the future.

So, the past is really gone, and the future is really a mystery. Only the present really exists... now.

And this is always true.

Phil Warnell said...

Hi John,

“So, the past is really gone, and the future is really a mystery. Only the present really exists... now.”

First let me make it clear that my following point is meant to find clarity and not serve as a challenge. That is you leave the impression that in QM the “now” is a place where uncertainty is resolved and yet it is only at the “now” where uncertainty is relevant; for in the past it collapsed to be resolved and in the future is potential. The “now” however has neither resolution or potential, as this is where uncertainty exists as relevant.


Regards,

Phil

Bee said...

Hi John,

Yes, it is a purely classical picture. I meant to explicitly point it out but apparently forgot. You can put free will and an open future into QM.

I don't get what you're trying to say with the 'here'. I have the impression you're making fun of me, but not sure why. Whether or not two points are identical is a well defined question on a manifold. What 'existence' means isn't. As to who you are or aren't this again involves a fair amount of macroscopic phenomena. I have repeatedly said that I didn't even attempt to 'settle' any question, I've just written down my opinion on why I doubt that our experience of a 'now' is a fundamental property of nature. I also said I doubt one can settle this question with the knowledge we have today for exactly the reason that there's no such concept as 'existence' in our theories (and very possibly this will remain so). I was writing the above mostly because I find it an interesting topic and I thought one or the other reader might find it interesting as well.

Best,

B.

CapitalistImperialistPig said...

Bee,

My real problem with the idea that the present is an "illusion" is that it uses the word 'illusion' in a much different sense than the usual sense.

John Baez says that block time fails because of quantum mechanics, but I think that the details he invokes really have more to do with relativity. The laws of quantum mechanics evolve the wave function deterministically, but when you single out a "now" by making a measurement and collapsing the wave function (however you want to call it) information leaks out of your light cone.

Of course we can "change the future." That is the point of senses and nervous systems. You might say that "choice" is an illusion fostered by the amplification small signals (like my feeling of fatique) into larger ones (like going back to bed), but it's still leads to a behavior pattern pretty different from that of my refrigerator.

Bee said...

Hi Qubit,

Then how come we can make measurements in quantum mechanics, but not 'unmeasurements'? Best,

B.

Bee said...

Hi CIP,

Yes, that is true, the use of the word 'illusion' in this context isn't quite what people usually mean with 'illusion', but I hope I made clear in my post what I mean before I used the word in the last paragraph.

Regarding the future: what I meant to say with this remark is that there is no way you can prove you can change the future, just as there is no way you can prove you have a free will. Therefore a conclusion of the kind 'We can change the future but not the past, therefore the future is different from the past' is based on an unprovable assumption and not good for anything. This is pretty much the same question as to why people read horoscopes. They either predict the future, but then it's a prediction and you can't change it anyhow. Or you can change it, then it isn't a prediction. So what's the point? Best,

B.

Bee said...

Hi Neil,

but I just don't accept the block universe or any treatment of time which tries to "denature" it or hollow it out into just something about space/s and structures in the end.

This actually doesn't surprise me. It surprises me instead that in the poll such a large fraction opted for the block universe. I am not sure if they actually realize that it implies you can't change the future anymore than you can change the past, meaning there also is no such thing as free will.

Here is a question for you: Consider it was indeed true that free will doesn't exist, our future is completely pre-determined, and that at some point we have evidence supporting this point of view over the contrary one. Do you think humans would ever be able accept such a theory as true, or would they deny it to protect their self-perception?

Best,

B.

Bee said...

Hi John,

The common sense view of time doesn't fit just cause of relativity where your refernce frame can change the order of events.

This is the argument of the previously mentioned paper by Petkov. However, I think the conclusion is wrong, but this would be a rather lengthy explanation.

As to the 'now' of massless particles, it is an interesting point (sorry I didn't reply to your earlier comment). One could ask then whether massive particles are necessary ingredients to form structures as complex as our brains (I'd guess so) that can order events in time.

Best,

B.

Bee said...

Hi Phil,

What you now have forced upon me is to follow up on the other Smolin lectures,

Gee, it certainly wasn't my intention to force Lee's lecture upon anybody.

Btw, I am not sure we differ on the points you bring up. I too would say that time plays a special role. I wouldn't quite say it is what makes things 'dynamical' for this seems to be a tautology, but simply speaking a sign can make a big difference in a differential equation. I don't think this is in disagreement for what I said earlier (or if it is, I fail to see how so).

I admire that your would just come out and reveal to all what you current thinking is, as to the nature of time and what part consciousness plays if any.

Well, I mostly use this blog to dump all the stuff I think about but that you wouldn't find in my papers. On the one hand it's always interesting for me to get some feedback, and I hope that on the other hand it's interesting for the readers as well. Best,

B.

Arun said...

Yet, if you look at some law of nature or a theory describing the evolution of a system, there is no such thing as a present moment there. You can have a time in that description, and to every time you have a configuration. But all of these times are equally there or not there, none of these moments is special.

I have some disagreement with this. In QM, there is a special time, when the Schrodinger equation of the (isolated) system no longer holds and the system approaches a measurement situation.

I release a single photon into a diffraction apparatus, and all instants are the same until photo-detection is involved. Then something radically different happens. There are special eras our theory of QM.

wolfgang said...

Bee,

nice picture(s).
It works well if physics is deterministic (as John pointed out).
If you want to handle QM you are more or less forced to a many-worlds philosophy.
I assume you believe that the different branches of the many-worlds interpretation equally exist? No matter how small their probability?

As for John's question about the 'here'. You discussed past, present and future so far. What about 'space-like' events. And what about events beyond an event horizon?
I assume in your 'block (many-) world' they exist in the same way as the present...

X said...

Bee:”I do not think the fact that we perceive the 'now' as being different from the 'then' is a fundamental property of nature, but rather a consequence of the way our brains store and organize information. We are able to store past experience in a memory, and information is perceived differently depending on how old it is. The present moment plays always an especially important role, but this is a subjective experience. In a nutshell this is why I believe the flow of time is an illusion.”

Let me ask you something.
Consider the following gedankenexperiment: you are rigidly confined to the chair inside the completely dark room without any communication with the outside world; all your biological subsystems are maintained continuously with the constant parameters.

What do you feel? (The question addressed also to everybody who want to answer).

Regards, Dany.

Plato said...

CIP invoked the lightcone, how nice:)

Enrique's conceptual integration is very appealing to me. It is a synthesis of "all the information" into a conceptual framework.

The complexity of the situation sees a mathematical basis to all expressions, "could be the spot" where such probabilities present themself then:0?

While I may have pointed to "the ridiculous in the dream relations of Pauli and Ramanujan," they still worked the routes of science, but were held in a "psychological state then" that few would say exists.

Yet, we do become confused sometimes.:)

So is it humanly possible ever to relate the singularity in our endeavours as human beings, that such consolidations metaphorically could represent such chaotic states as well? New beginnings?

What is to come out of it if all information is never lost? What we are we not aware of?

"Now" then, is a "ever becoming?" Includes the past as well, no matter how hard you try to delineate from it.

Reductionism, while we look back to the beginning of the universe, this is a deeper recognition of what and how this information manifests in the new universe?

I've invoked an imaginary "Glaucon" for obvious reasons.:)While from Plato's stance he could have been used as a "moral compass," and it was "this use" that pointed to "new directions?"

Sometimes "these figures" are already embedded in our makeup, whether you like to think so or not. "Such loops" are necessary, to see through "the finer print of the analysis?" A "self evident realization" of what analysis can do when we think hard about what is to come next.

That "every now and then" takes on a "whole" new meaning because there is already something embedded in the design and makeup? Who knew?:)

Plato said...
This comment has been removed by the author.
Count Iblis said...

I think Jon Baez's argument can also be turned around a bit to argue in favor of the reality of the past/future. The fact that there exists an operator for the elecron's future position at all means that in principle you could observe it.

The wavefunction would then collapse into a state that will evolve to a Dirac delta after some time.

QM effectively makes the future and past as real as different sectors of the wavefunction which, according to the MWI, exist.

If we keep a quantum system isolated, then all the information about the past is still in there. So, if we put John Baez in the position of Schrödinger's cat and wait until many half lives of the atom have passed, we can, in principle, still discuss mathematical physics with John.

Plato said...
This comment has been removed by the author.
X said...

John Baez:” For example: according to Schrodinger's equation, the position of an electron now does not commute with its position at any other time.”

???

According to Schrodinger's equation the position of an electron in the stationary state for example is the same all the time. Any operator commutes with itself.

Regards, Dany.

Count Iblis said...

X, John is talking about the operators:

x(t) = U-dagger(t)x U(t)

where x is the observable for the position and U(t) is the time evolution operator:

U(t) = exp(-i H t/hbar)

X said...

John Baez:” In other words: from the viewpoint of our "now", a bunch of information about the past is really gone - so completely gone that it doesn't even make sense in principle to ask exactly what happened. Same with the future.”

Each outcome of the measurement may be used to define the initial conditions. Repetition of measurement using indistinguishability- the essential feature of the Quantum World – allow one to reconstruct the distribution (field) required for the description of the future unitary evolution of the system using PDE (you also need well defined boundary conditions). However, the process apparently is not reversible; you can’t prepare the quantum system using bunch of classical systems (statistical ensemble).

Biology, human memory, human brain etc. is not an area of my competency, but our memory is approximately deterministic (usually based on facts- measurements, it is very difficult to remember dream for example), our consideration of future reminds me standard structure of the Hilbert spaces.

Regards, Dany.

P.S. Hi Count Iblis, I knew that. So? Substitute x(t+a). Come on! Now we discuss the existence of the stationary states?

Ed said...

How much of this is from Lee's lectures?

Neil' said...

Bee, I think most people want to accept free will in some sense, as well as the reality of time (versus being "an illusion", but just what does that make something into? I think that concept has become a silly throwaway evasion.) Most wouldn't accept complete determinism even with overwhelming evidence. I'm not sure if I would (heh - but whether I did or not would be predetermined!) In any case, we already "know" (except for those posing the decoherence philobabble end run) that the universe isn't deterministic - all we need is a way to make that holistic to our minds and not just a pile up of microscopic uncertainty.

Also, I don't agree with those who say the block universe isn't credible due to lack of determinism etc. I think that you don't get the fundamental idea, which is simply to represent the entirety of history as a block a priori of the particular causality issues. It has nothing to do with whether the structure in the farther "future" end of the block is determined by previous structures. Indeed, the block could just be disconnected events and that would just be what happened.

I don't believe in the BU, but I must admit that relativity of simultaneity makes the notion of a true "now" to be problematical. I think the best answer is, time is real but for each local process or "physical clock", so there's no need for them all to match up to some uniform "simultaneity." BTW note the irony that a big bang sets clocks running all over, to get back the common synchronicity more or less of "cosmic time."

x: What you "feel" in the dark room is the bare fact of your existence, which maybe shouldn't even be called a feeling but which is a conscious experience of a very abstract type. The mystics seek this out. If you wonder how can consciousness not have content, then how can space not have specific objects inside (was Descartes right about the impossibility of a true physical vacuum?) If you really want to have fun, look up "modal realism" which points out that no formal logical definition can separate "real material worlds" from the mathematical models (to the extent they apply - but they don't, fully) used to describe them.

Bee said...

Hi Ed,

I only went to the lecture on Jan 9th and to the one on April 2nd. What I wrote above about the memory etc is not mentioned in one of those.

Hi Dany,

I would probably feel the urge to get out of this room. I don't know what you're aiming at? I said above that the capability of the human brain to judge on the passage of time is rather imperfect and depends on the sensory input. The way I used the 'memory' it is a fairly general concept, so I am not sure in how far such considerations are relevant?

Best,

B.

X said...

Hi Bee,

Bee:” I don't know what you're aiming at?”

I am curious what one feel in that situation. Perhaps, loose sense of time and space. I don’t know. Recently I read that it was Feynman’s hobby to perform that experiment on him self.


Regards, Dany.

Neil' said...

I don't agree with John Baez's apparent take on the implications for the realness of the past, per the current measureability of what happened then. He wrote:

In other words: from the viewpoint of our "now", a bunch of information about the past is really gone - so completely gone that it doesn't even make sense in principle to ask exactly what happened. Same with the future.

So, the past is really gone, and the future is really a mystery. Only the present really exists... now.


Well, maybe he meant it was just gone in practice. So sure, a bunch of info about the past is really gone - but that doesn't mean that what happened then is literally vague, or especially that it was vague then. Consider if we commenters were talking together in a room instead of posting. What we said would be quickly lost in quantum fog of the atmosphere, even minutes (?) later there wouldn't be a clear physical record (well, gravity waves from our larynxes? - but that could be scrambled with noise from around us.) Let's say we record just a portion of the conversation on tape.

OK, the taped part would be considered a reflection of "what really happened", but the rest would be just a figment in our memories - you think there would literally be a distinct period of definite talk, then "vagueness" just because later, we couldn't prove what was said after the tape? And maybe the tape is doctored etc. (that reminds me, what effect do unreliable detectors have on quantum measurement?)

While you are talking and experiencing things, you know there is a definite flow of events (to within current standards of uncertainty) so I just don't buy the idea that the past is literally indistinct. However, John apparently has distinguished company: didn't Einstein and Tolman (of the now much forgotten "right-angle lever paradox") write a paper stating that quantum uncertainty meant there literally wasn't a definite past?

Ironically, in a real block universe the worldlines are all just sitting there and trans-temporal knowledge supposedly has nothing to do with it. I think the worse problem with the block universe is, the issue of how to represent the universe anyway, apart from issues of time. I mean, how does a wave function "really" expand and then collapse? Whether time flow or a block, how do you represent it? And don't just say it's about our knowledge - then, what does the electron "really do" etc?

BTW, Iblis, I hope you will put a new post up - I need good blogs to comment on. Cosmic Variance apparently banned me, for nothing worthwhile in particular (I sure didn't make derogatory remarks or etc.) I've asked them for relief and hope for same.

stefan said...

OK, bringing up quantum mechanics makes things even more complicated, and this was probably not at all intended in the post...

But since we're talking about it: I'm a bit confused by the mentioning of the Schrödinger equation - this is a non-relativistic theory, so I do not quite see how this fits in a discussion of the block universe in the SRT context? And if we talk about relativistic quantum field operators instead, they usually do commute at different times, don't they?

Best, Stefan

Count Iblis said...

Hi Neil,

I have a few ideas for a new blogposting, so check in a few days.

Stefan, local operators will (anti-)commute if they are spacelike separated.

If everything were to commute at different times you could write down a state vector that is a simultaneous eigenvector, but that can't be the case as that would imply deterministic time evolution.


X, I don't understand what you mean. You can't write down a simultaneous eigenfunction of x(0) and
x(t). Or, put diffently, a wavefunction that is intitially a Dirac delta won't evolve under time evolution to become a Dirac delta some time later.

Ned said...

Dear Ms. Sabine,

as far as I can see the question you are "anschneiding" here (don't know the english expression) is not physical, but metaphysical - in the original sense - it goes beyond, it addresses something more fundamental than physics.

To answer it one has to be radical - this also in the (meanwhile forgotten) original sense - radix meaning root, so that means one has to go to the roots. And there's the problem.

Reason for that, and also addressing your remark: yes, you _are_ a victim of your education - that's no suprise, almost everybody is - but this goes much deeper than one realizes. That means you, and everyone else, is so deeply conditioned that being radical, meaning really going to the roots of a problem is almost impossible for everyone. The society we've been brought up in has seen to it that one doesn't dig too deep.
People live in a thick web of illusions, and their investments in this artificial world are just too big. You won't get any help if you try to get rid of your own illusions, quite the contrary - other people will feel threatened, because then what will happen to their own illusions ... they might have to take a closer look at them, too ... so to prevent that they will attack you in any way and stop short of absolutely nothing.
That's also nothing new - just take a short look at history - it's just something we like to forget most of the time, because it is a not very pleasant reminder of the society we live in.

So better stay with physics and don't try to really get to the root of things, whatever that might be - that can be really dangerous, in _any_ sense, and you will be _very_ alone - so alone that you cannot even imagine how. Physics is (relatively) safe, and socially accepted - of course you'll have to forget about getting rid of any illusions, but so what - at least you will get lots of help in maintaining them - all your friends and aquaintances have them too, and they will convince you, and themselves, that these are not illusions, but cold, hard facts; so at least you won't be alone, and that's something, too, I guess.

Neil' said...

Ned, your rundown of your weltanshaung regarding illusions and the roots of reality is dazzling, but what is your actual opinion on the current subject?

BTW, usually most physicists and some reductionist philosophers think that it is everyone else who lives in a world of illusion, but I think there is great unexamined irony in all that (for example, the way that some philosophers of mind reject "folk psychology" while working off the "folk epistemology" underlying naive realism.)

Plato said...

I remove two posts to help retain some of the consistency expressed and those following. I just wanted to say that one of the links is explained here.

I thought for sure I had nailed down the idea behind the point of the thread, other then what was written. Sorry Bee.

Just because one can't remember dreams does not mean they do not exist. I again point to Wolfgang Pauli and Ramanujan again.

Lee has had a long association with Rovelli and Barbour(philosophically in regards to time) and the issues of time are relevant in the way he produces this lecture in relation to consciousness and the universe, I referred too.

The gravitational collapse had to be relevant in association to the universes heat death(?), as well as the sleeping that goes on, and when times become chaotic and confusing, growth still does emerge, not just in the biological sense in terms of the evolution?:)

Anonymous said...

For me, Hartle's discussion mentioned earlier

http://arxiv.org/abs/gr-qc/0403001

reduces the problem to understanding why there is a difference between the past and the future in the first place. Or, to put it another way: your solution to the problem of "now" will be completely conditioned by your answer to the problem of temporal asymmetry. Would there be a "now" if there were no arrow of time? I guess not. Do you, SH, have a post on that question? I'm sure we would all enjoy an essay on that theme.

X said...

Hi Count Iblis,

You use Heisenberg picture. I guess JB comment was a joke.

Regards, Dany.

Bee said...

Hi Ned,

Thanks for your interesting comment. I actually cherish my illusions very much and don't want to get rid of them alltogether, I guess it's the only thing that ties me to sanity. I think what you are saying is true to some extend, see my above question to Neil. I'm not sure how far people would actively go, but I think it is certainly the case that passively there is a selection of topics in the sense of interest and financial support which has very real consequences but this isn't quite as deliberate as you make it sound.

What you write reminds me of a quote from Homer-Dixon's book I used earlier:

"No matter how much we believe in our institutions and in the regularized procedures of our societies, no matter how just, rational, and durable we think them, they are at the best only loosely grounded on some form of bedrock reality or immutable truths that endure beyond human beings. To a considerable degree, they are sustained by collective belief and consensus, by tacit, unquestioned, and often grossly simplistic assumptions about how the world works, and often by mutual and willful self-delusion. Our societies cohere and function in no small part because most of us want them to cohere and function, and because the alternatives are, for most of us, literally unthinkable.
We all eagerly assume there exist people, somewhere, who unlike ourselves do have a grip on the bedrock reality that underlies our societies, who understand how things work and will take care of us if severe problems arise. We also deeply fear the possibility that it isn't true [...]"

And I am afraid that this fear stalls progress that would be desperately necessary. Best,

B.

PS: 'Thema anschneiden' -> to touch on a subject

Bee said...

Hi Anonymous,

Would there be a "now" if there were no arrow of time? I guess not. Do you, SH, have a post on that question? I'm sure we would all enjoy an essay on that theme.

No, I don't have a post on the arrow of time. I'll keep it in the back of my head, but since I haven't quite made up my mind about the topic, I'm reluctant to write about it (I mentioned at some point I went to this workshop last year, but it wasn't very illuminating). Only from what I wrote above I see no reason why it should not be possible to have a 'now' without an arrow of time (consider your memory function to be symmetric, it can still have a peak), yet time wouldn't seem to 'flow', and I doubt without an arrow of time you'd have some kind of evolution that produces systems with memory.

Best,

B.

Bee said...

Hi Neil,

I don't believe in the BU, but I must admit that relativity of simultaneity makes the notion of a true "now" to be problematical.

Well I don't think so actually. That's what I meant with footnote [2]. Maybe I should write that down at some point.

Hi Wolfgang,

As for John's question about the 'here'. You discussed past, present and future so far. What about 'space-like' events. And what about events beyond an event horizon?

John's question wasn't whether these events exist (that I might have understood), but whether they are 'here' (which doesn't make sense to me). See, I have a problem with the concept of 'existence' to begin with, this is possibly one of the reasons why I favor that 'everything exists' (upon which you can basically forget about the concept alltogether). One can ask whether something is, was or will be observable, but existence is a fairly elusive idea that echos back on us in all the multiversions. The reason why I've been using it is just that it seems to be a central ingredient to the 'presentism' for you have to distinguish the 'present' moment somehow. That's why I said I don't want to explain what existence is but whether there is a property (call it 'E') that makes the present moment different from all other ones (it is no coincidence that this sounds suspiciously like a timelike slicing). Best,

B.

Bee said...

Dear Arun,

I have some disagreement with this. In QM, there is a special time, when the Schrodinger equation of the (isolated) system no longer holds and the system approaches a measurement situation.

Yes, but you could do that for any time. When I said all times are equally special or non-special I didn't mean that there can't be no events happening at certain times and not others.

Btw, regarding your comment at the previous post:

Special Relativity also tells me that when I try to extend my present moment to a global plane of simultaneity, then it is subjective. Given any two events in this extended present that I consider simultaneous there are observers who will find them in either time order.

That is essentially the argument in that paper I mentioned. I still don't think this conclusion is very strict. Maybe then I should really write another post, it might be kinda controversial though. Best,

B.

Phil Warnell said...

Hi Bee,

I guess to call time the dimension that is responsible for what makes things dynamic is somewhat redundant and yet strictly speaking GR contains no such claim per say. The other thing that I find to be a sticking point being those that insist that Quantum Theory as indeterministic and then close the door via this statement. The truth being that this also is still somewhat an open question for a few.

I believe Smolin’s true interest in all this is he feels we won’t be able to develop a consistent theory of Quantum Gravity or unified theory if you prefer unless such questions are considered. Personally I have held this opinion for some time although I admit it relates more to only a feeling rather then intense consideration. The order of events as opposed to reference frame as noted is another of these sticking points and I find it interesting that you don’t find this to be much of a problem. I then will be interested how you propose to dance around this one, as I understand this to be a bit of a red herring as well.

Best,

Phil

Garrett said...

Please refer to my future comment on this topic.

Ned said...

Dear Ms. Sabine,

thanks for your kind translation!

Back on topic:

A physicist (*) is travelling in a bus.
Looking out of the window, he notices a clock showing the time: 9:30.
A short while later he looks out and sees another clock, which shows the time as 9:15.
"My God!" he cries out. "I must be travelling in the wrong direction!"

_ _ _ _ _
(*) no offence meant!


To Mr. Neil:

It is a question belonging to metaphysics and not to physics, as I already said. So what can one expect as an answer - maybe "43", for a change?

Andrew Thomas said...

Paul Davies's superb Scientific American article called That Mysterious Flow tells you basically everything you might ever want to know about the block universe.

The main argument in favour of the block universe (as some have suggested) comes from special relativity and is called the Rietdijk-Putnam argument. This argument considers the function of the "now" in the tensed theory which is to turn the unreal future into something real. However, observer-dependency in special relativity means that some events are in the present for some observers (i.e., real) but still in the future for other observers (i.e., unreal). How can an event be both real and unreal?

Bee, your ideas on the brain storing recent information and discarding old stuff was basically suggested by James Hartle with his proposed "IGU" system - see the "human robot" diagrams with information registers in this New Scientist article.

As far as John Baez's comment is concerned regarding electron positions and QM, surely all we need be concerned about is the STATE of the electron at any time, not its precise position. And the evolution of the state vector is deterministically described by the Schrodinger equation, so I don't see why anything there precludes the block universe model.

Bee said...

Hi Andrew,

Yes, the Rietdijk-Putnam argument is also mentioned in the article by Pevkov.

I didn't consider anything of what I said new or original, it's too obvious for that.

Best,

B.

Andrew Thomas said...

Yeah, you're right. I always thought James Hartle's idea was rather obvious, so I wondered why there was quite such a fuss about it. I'm sure it would be obvious to any computer programmer (as opposed to physicist) that the brain is likely to process information and store it in memory like that.

Bee said...

Yeah. Thanks for mentioning Jim, I didn't know that work of his, will give it a look. Best,

B.

Neil' said...

Andrew, deeper reflection upon the problem of the wave function shows it is more problematical than it seems. Simplistically, "given" a WF it does evolve deterministically until it collapses. However, in what sense is it "given" for us? That's what we do with the mathematical representation when we work with it, that doesn't mean we can find the shape of the wave. Indeed, we are not supposed to be able to measure the wave itself. We are only supposed to be able to test it under the condition of getting probabilistic results (implying the need for an ensemble!) of checking for eigenstates (if I've got that framed right) - IOW, we can make a photon to be "linear polarized at 20 degrees", but one just popping out of an atom has to be tested by e.g. calcite beam splitters for chance of showing x or y or RH or LH polarization. Furthermore, we still don't know the absolute phase of that linear photon, and the details of its Fourier composition ("how many wavings" it has: its coherence length.)

(BTW, I think Yakir Aharonov is right and we can measure the WF, my own newest explanation will appear soon at my linked-out blog. But that isn't the orthodoxy.)

Hence we have to wonder what specific WFs are out there to begin with, it isn't like zoologists taking pictures of animals and knowing here is a zebra running SW, there goes a horse running W, etc. The knowledge of the WFs is itself indistinct, unless we carefully crafted them ourselves! (This disconnect should get more attention than it does.) If that's so, then also the precise evolution is in doubt, since the mathematical modeling also depends on precise perturbations and interactions, does it not? Well, if that is not distinct either, how can the evolution be definite?

Then there's the problem of collapse, and what to do with the WF then. It can't really be modeled; ironically think of simultaneity problems for "immediate" collapse. Then there are messy issues like the Renninger negative result type collapse (which reallocates the WF to the region it can then still be in), the problem of how unreliable detections affect the WF, etc. As for decoherence, I think it is a crock since waves, whether coherent or incoherent, are going to stay waves unless localization is forcibly "put in by hand." Whatever happens to the waves just isn't going to specify a little "hit" of a photon flash on a screen (use the simple cases, then you have to deal with the basic collapse of a simple wave.) As you indeed wrote at your QM/reality site:
So decoherence solves the mystery of apparent wavefunction collapse, and also explains why we do not see superposition states in macroscopic objects, but it does not explain which particular eigenstate is selected during the "measurement" process.
But that is the real collapse problem anyway! You haven't really solved the original question. I still like the site.

Neil' said...

To better clarify; a revised sentence:

That's what we do with the mathematical representation [of a wavefunction] when we work with it [in a modeling exercise], that doesn't mean we can find the shape of [an actual wave in the real world.]

Plato said...

Anonymous Garrett said...

Please refer to my future comment on this topic.

Look at the E8 process and what are we to learn of it's developmental process and all that it impart to E8.

If you knew all the probability of actions of the future in regards to E8, then it is connected through your statement now? :) This is important in relation to Marcus Chown's article.

Andrew the future and past have to caught in a "self referential loop."

The Scheme is important as a mapping process but it's what behind it it that I speculate, and had further mesning.

Andrew Thomas said...

Hi Neil, thanks for your response. Yes, if you want to want to get into a discussion of what the wavefunction actually is (a "real" thing? Or just a mathematical tool we can use to solve real-life problems) then you open up the usual can of worms, and that's really beyond the scope of Bee's article. Maybe Bee might want to write about that subject at some point.

I was really just trying to answer John Baez's idea that quantum theory somehow invalidates the block universe model. I don't see how it does: at any moment in time an observer gets can measure the STATE of the universe around him/herself. That state will include the positions of some electrons we have measured, and also the state of electrons whose positions we have not measured (for which we have to describe by just a state vector or "wavefunction"). But either way, we can find the state of the universe. And the block universe is just a "stacking" through time of all those states for all observers, i.e., there is no moving "now" point, there is just the total sum of everything that has ever existed, and everything that WILL ever exist, and all those things have an equivalent level of "reality". Everything throughout all time being equally real (the same "ontological status").

We just get the impression of a "now" point, through the process which Bee described very well in her original article: "In every moment, the moment itself is 'special' in that it is the most recent and most prominent experience, yet this is the case for every moment".

X said...

Ned:” A physicist (*) is travelling in a bus.”

Local variation:”D.L. is traveling in a car on highway and receive call from his friend. “D. be careful, it was reported on radio it is out there a mishigener traveling in the wrong direction.” “Big deal. I see here thousands of these.”

Regards, Dany.

Serenus Zeitblom said...

Bee said:
No, I don't have a post on the arrow of time. I'll keep it in the back of my head, but since I haven't quite made up my mind about the topic, I'm reluctant to write about it

That's not a good reason to refrain from writing about it! :-)



Only from what I wrote above I see no reason why it should not be possible to have a 'now' without an arrow of time (consider your memory function to be symmetric, it can still have a peak), yet time wouldn't seem to 'flow',

But if there is no arrow of time, nothing ever happens, so you would not be able to determine whether a given memory was fading away or not! Indeed, when you are in an aeroplane, because you cannot see that you are moving and nothing ever happens, you "lose track of time". In fact, I guess that the subconscious difficulty to establish a "now" on a plane is the reason why plane travel is so unpleasant --- your brain struggles to do its usual job.....



and I doubt without an arrow of time you'd have some kind of evolution that produces systems with memory.

Oh sure, if there were no arrow of time at all then certainly we would not exist. I was thinking more in terms of a localized system in which the arrow of time is less obvious eg a prisoner in solitary confinement, or you on an aeroplane, etc.

X said...

Serenus Zeitblom:” if there were no arrow of time at all then certainly we would not exist”

Sure, the question is who is right: Einstein, Rietz or both?

Neil':”I think Yakir Aharonov is right and we can measure the WF, my own newest explanation will appear soon at my linked-out blog. But that isn't the orthodoxy.”

Yakir is wrong. The statement contradict AB phenomenon which was unambiguously confirmed by A.Tonomura et al. WF is not observable, in addition the observable should be gauge invariant quantity to be measurable.

You should understand one simple thing: the language of explanations in physics is math only. I mean you may do what you want, but don’t fool yourself: your thinking never will be accepted as “explanation” (and I suggest you to read and understand Dirac, von Neumann and Wheeler&Zurek books before thinking).

Regards, Dany.

Bee said...

Hi Serenus,

But if there is no arrow of time, nothing ever happens, so you would not be able to determine whether a given memory was fading away or not!

Notwithstanding the question whether in such a case intelligent beings could develop or whether one could convincingly speak of 'thinking' I believe you are are understanding 'fading' as necessarily being directed backwards (to the past), which doesn't have to be the case. You could in one point have 'fading' knowledge into both directions, past and future. Maybe you would want to call that differently though. If this is hard to imagine, think of it as a spacelike direction. Best,

B.

Neil' said...

x: Physics can't just be doing math, because it needs to connect to something. Eq. f = ma is just algebra and could have been m = fa^3 or anything, it's understanding "f", "m" and "a" that makes it physics. Physicists have to use philosophical style reasoning to state what they are referring to, how to interpret experiments etc. If you look at the arguments supporting decoherence, they have to make an argumentative case and can't just present "math" in a vacuum. Once they do that, their logic can be addressed semantically in terms of fallacies, structure, etc. Yes we can predict the chances of something happening in QM, but we have a *real* problem mathematically modeling the wavefunction as a wave because we can't figure out what happens to it when a measurement occurs. What should be a "physical" question has become "metaphysical" not by a philosopher choosing to discuss traditionally metaphysical subjects like ethics and God, but because the physical universe really doesn't make sense when we try to model it.

The argument I have made concerning measuring the WF is ultimately based on the math of interaction of waves and object. Also, if you read his papers on weak measurements you will note that distinguished physicist Aharanov (one of the team in that very AB effect you mention) uses sophisticated mathematical arguments to make his case, not just e.g. quotations from Plato or his own hunches. I don't agree with your argument) on AB anyway (which you made using words, not pure math - see?) The AB effect is mostly about the effect of the magnetic vector potential A field on moving electrons, and I don't see how that prevents knowing more about wavefunctions.

Note the supreme irony that the Post subject, the argument stating that "time doesn't flow" and we are really in a "block universe", has no special math treating "t" any differently. It is just a metaphysical argument in effect over how to imagine what's going on! (Or, heh, that there really isn't a "going on" after all ...)

Plato said...

So Neil, what does the "scheme represent" in terms of the computational, the mathematical sense, in relation to consciousness?

If link above does not work, do search on "scheme and wikipedia"

Currently there is no organ that represents the time function in the human brain?

If one is to squeeze consciousness down to it's singularity, then what will manifest as we learn the heat death is not the end of it. The brain is quite capable of seeing further then it did before in it's reductionistic pursuit? Look at the elaborate frame we have constructed using the standard model? The window to reality is much more in depth?

Where are we headed?

So we have come to a complex question about the singularity? About consciousness? The Now?

X said...

Neil':”we can't figure out what happens to it when a measurement occurs”

That is off-topic here. If Bee will start separate discussion about that I promise to explain what the problem is and what the preliminary solution is.


Neil’:” if you read his papers on weak measurements you will note that distinguished physicist Aharanov (one of the team in that very AB effect you mention) uses sophisticated mathematical arguments to make his case, not just e.g. quotations from Plato or his own hunches.”

Dear Neil',I know Y.Aharonov personally more than 30 years (Aharonov, not Aharanov).

Regards, Dany.

X said...

Hi Bee,

Bee:”We all eagerly assume there exist people, somewhere, who unlike ourselves do have a grip on the bedrock reality that underlies our societies, who understand how things work and will take care of us if severe problems arise”.

Today is our Independence Day. Each one of us contributes anonymously and according to his knowledge and ability. Don’t worry, we know our job and now we also know how defend ourselves and others.

Plato:” Just because one can't remember dreams does not mean they do not exist.”

Who said we can’t remember dreams or that they do not exist?

But better we remember pictures. Our memory is obviously quantum (set of 3-D holograms connected by ‘scalar’ time tag, 4-D world.). We don’t need all that speculations. Just sit down and write math of that without human brain and without consciousness.

Regards, Dany.

Plato said...

Dany:We don’t need all that speculations. Just sit down and write math of that without human brain and without consciousness.

Yes Dany, I know what is required.

But they are more then speculations, even while they are subjective to you. I am speaking of something I do know.:)

I am a student, yet, we live "experience" and underneath the realities, the math you talk about.

I hear it often, does not make one ignorant of what is required?:) I also pay attention to what scientists are doing too. I am learning, and trying.

Dany:Who said we can’t remember dreams or that they do not exist?

Those Dany who do not dare venture farther then the waking reality. It is of a subjective nature, and again what is the blog for, if this is not for science at it's best, but to share other ideas that do not fit? :)

Some mathematicians write stories according to their views. What's with that? It could be mistaken for "experience or fantasy" of the worst kind?:)Yet, only those that understood this relation might have been able to put both together?

Neil' said...

Plato: I don't know much about "scheme" per se, if you are talking about the mathematical issue e.g. in Wikipedia. I don't however see a literal block producing even an experience or "illusion" (what a cop-out IMHO) of flowing time. But the idea of objectifying the universe into an unconditioned "way it is" just doesn't cut it for me. The nature of reality is literally relative, it is different depending on how you look at it etc. I don't think the BU is so much "wrong" as just a false idol of absolute character (aww more "metaphysics," but remember that those who critique metaphysics have to use the same to play the game.)

As for time-organ in the brain, there is something that tracks the sense of duration. One person with damage in that area, is said to not see cars etc. "moving" but just finds them closer looking at later times etc., won't even cross the street. To me the supreme irony is for our mental process to produce some special new type of quality like "time" that is said to "not really exist" - that elevates us to being more than just a thing.

x: Pardon me if you didn't want your cover blown, but from your knowing Yakir Aharonov (pardon miss-sp. the second time around) so long so well (and maybe an "independence day" hint), and knowing physics, I suspect you are the head of a distinguished university in Israel (Wow! In this humble thread ...) I just can't find another "Dany" when googled along with "Yakir Aharonov" to fit the bill, so nothing special about my sleuthing.

Well, you didn't say that you thought his arguments weren't very rigorous, just that you would know if they weren't. (We aren't very impressed with "the argument from personal authority" around here, we are looking for some reason to agree or believe - if doable with math then so much the better.)

X said...

“Who said we can’t remember dreams or that they do not exist?”

I was playing with words and had in mind J.B.Hartle quant-ph/0610131.

Plato:”Those Dany who do not dare venture farther then the waking reality. It is of a subjective nature, and again what is the blog for, if this is not for science at it's best, but to share other ideas that do not fit?”

Sure, but I have other ideas what is science at its best which do not fit yours. All that “ideas” don’t looks to me new and productive. Physics should “stand on shoulders”.

Plato:” But they are more then speculations, even while they are subjective to you. I am speaking of something I do know. I am a student, yet, we live "experience" and underneath the realities, the math you talk about… I also pay attention to what scientists are doing too. I am learning, and trying.”

All I want to say is: pay attention and learn what scientists did too (during last 500 years). I suggest to you to read carefully Ned comment 8:34 p.m., May 04. I find it very deep.

By the way, I did mistake: it was Bee’s quotation from Homer-Dixon's book and not her own words. Therefore my back reaction lost content.

Regards, Dany.

Plato said...

Dany,

At least you recognize the association of the "back reaction" and now, using it to point to Ned, wonderful:)

Dany:I suggest to you to read carefully Ned comment 8:34 p.m., May 04. I find it very deep.

Okay, now in back reaction mode.:)

Ned:So better stay with physics and don't try to really get to the root of things, whatever that might be - that can be really dangerous, in _any_ sense, and you will be _very_ alone - so alone that you cannot even imagine how. Physics is (relatively) safe, and socially accepted - of course you'll have to forget about getting rid of any illusions, but so what - at least you will get lots of help in maintaining them - all your friends and aquaintances have them too, and they will convince you, and themselves, that these are not illusions, but cold, hard facts; so at least you won't be alone, and that's something, too, I guess.

Dany if ones need the "castle walls" in which to feel "safe" then that is what they need. If they do not feel they will be "socially accepted," then they have one strike against them already.

What kind of life is that to be afraid of venturing into the world, and then, be told that you should act a certain way, or we will not accept you. Is this some type of "social conditioning" that you like to apply to people and consider it deep?

No Dany, I do not accept your or Ned's perspective, and would not like to share that with those we want to venture further. Further, then the previous cultures had.

Many more minds available now Dany, and to think, that we are so alone in the cultural setting within the confines of some castle?

No, the times are very different, and even you may have played a part in the technological change, so, you are now "a victim of your own invention?":) What an "entangled web" we weave:)

Neil' said...

Dany, I actually do want to hear any detailed thoughts you might have on why the weak-measurement idea (that we can measure the rough "shape" of a wavefunction, not just find standard probabilities for collapse into either of the pair of orthogonal eigenstate we have in play) would be false. I suppose Yakir has his counterarguments too?
tx

Neil' said...

BTW, to amplify what I've said before: I think that saying, "time isn't real" is sort of (and maybe ironically) like saying, "Lorentz contraction isn't real." Well, there is a given, proper length invariant in its own way, but the contracted lengths are indeed "real" in relative terms. That's the sort of world we live in.

X said...

Hi Plato,

Plato: “Dany if ones need the "castle walls" in which to feel "safe" then that is what they need... What kind of life is that to be afraid of venturing into the world, and then, be told that you should act a certain way... I do not accept your or Ned's perspective, and would not like to share that with those we want to venture further. Further, then the previous cultures had.”

I am not afraid of venturing into the world. My favorite book since I read it first time at 14 was and remains Herman Hesse “Das Glasperlenspiel”. I need and use five universal Rules of the Game on my track. I never feel confined and I was already at 16 semi-professional mountain climber. My senior friends and acquaintances felt the same; these were not illusions, but cold, hard facts. I never felt alone. My video and audio memory from the past is presented here:
http://www.youtube.com/watch?v=QHgIG7R2Mds&feature=related
http://www.youtube.com/watch?v=2pZewiYyBG4&feature=related

Behind my words, metaphors and images stand the suggestion of the entire reformulation of the classical physics in terms of real Hilbert modules (dispersion free field theories) which is structurally connected with the sequence of the complex Hilbert modules, etc. I do not consider that a venture, it was first suggested by W.R. Hamilton and later by E. Schrödinger years ago. А имена тех кто здесь лёг: P.Jordan, J.von Neumann, E.P.Wigner, E.C.G. Stueckelberg, F. Gursey, S.L. Adler.

Regards, Dany.

P.S. When I finished my Ph.D.study my teacher Prof. L.P. Horwitz gave me a personal gift – his preprint version of J.M.Jauch book “Are quanta real?” During the study he used to call me Simplicio (another gift that deeply affect me was hand written manuscript of his Ph.D. thesis).

Plato said...

Quite the biographical sketch Dany. I am impressed:)

regards,

X said...

Plato:” Quite the biographical sketch”

I apologize for that, but I want you to know every Now and Then and not only small piece of it.

And now we are talking about undetermined future.

Plato:” I am a student, yet, we live "experience" and underneath the realities, the math you talk about.”

I talk to you, Bee and young generation of Castalians above the heads of present Dinosaurs: let us postpone the formulation of TOE at least to the next century.

Regards, Dany.