Thursday, March 15, 2012

Workshop on Nonlocality, June 27-29

I am presently organizing a workshop at NORDITA, Stockholm, on "Nonlocality: Aspects and Consequences." This meeting will take place June 27-29, briefly before this year's Marcel Grossmann meeting which is also in Stockholm.

The workshop on nonlocality is 3 days only, and we have about 20 participants already, so no more place for speakers. However, if you are planning on attending MG13 and are interested in the topic, you are welcome to attend. We can accommodate up to 35 people. If you are interested in attending, please fill out this registration form. And please forgive me for the website. I thought we don't need one but learned the meeting has to be listed in what appears on my browser like the world's most crappy looking conference listing. Credits for the logo go to Hans Mühlen, von und zu.

I am organizing this workshop together with Fotini Markopoulou. It is sponsored in almost equal parts by NORDITA and FQXi. I am really excited about this meeting because it's a topic that has been on my mind for a while, and I believe it has a large potential to move forward both the phenomenology as well as the theory of quantum gravity. Finally, here's the blurb, a true masterpiece of vagueness that is to say we'll figure out what we do if we know who'll be there:
"The workshop focuses on non-locality in quantum foundations, quantum information, and quantum gravity, including string theory and emergent gravity. The aim of the workshop is to bring together researchers working on various aspects of non-locality, to identify commonalities as well as differences in the role non-locality plays in different approaches to a fundamental description of space, time and matter."

16 comments:

Peter said...

Great topic IMO. Much better than all the time, time, time stuff. Hopefully you'll be able to post a simple, definitive, universal definition of (non)locality by the end of the conference.

Will there be PPTs, PDFs, perhaps even video posted? Please, at the cost of your conference appearing slightly less successful, for the sake of keeping a few people out of airplanes. Also, I can't afford to come.

Bee said...

Hi Peter,

I'll post slides online if it's okay with the speakers. There probably won't be no A/V recording, sorry about that. Best,

B.

Eric said...

Concur, great topic. I hope the conference moves out of the high energy particle regime and into the everyday regime a little. Instead of condensing theories of quantum gravity into the microscopic regime we should try enlarging it by moving principles learned from the standard model into the large scale regime. I believe some of these idea, such as weak force decay with energy release, also occurs in the long distance regime. After all the weak force really is just a form of non-locality that breaks down and releases energy. We already know that non-locality also occurs over long distances but is not stable. Connect the dots.

Neil Bates said...

Does nonlocality impinge on the issue of decoherence being responsible for the apparent classical macroscopic world? I would think not, but want to hear some opinions (after all, proponents of that view often invoke "entanglement" - but that looks to me like ordinary consistency of states along the chain of events in a component of the wavefunction and not genuine, non-local entanglement.) I've proposed an experimental way (quite unexpected) to test the oft-stated claim by strong supporters of the "decoherence interpretation" that decoherence effectively turns superpositions into mixtures (see name link.)

Arun said...

Dear Bee,

Sounds very interesting!

My uninformed speculations -

1.Suppose we accept that the laws of nature (e.g., Quantum Mechanics) are only descriptions of reality and not reality. So, the wavefunction of the electron describes the electron, but there is no actual wavefunction object out there any more than there is a probability distribution object out there for a coin toss.

2. We'd like our descriptions of reality to explicitly display locality.

3. However, when I serialize the pixels of a 2-dimensional image, or compress (e.g, zip) a string, I end up with an equivalent description in which the explicit locality is lost. In case of the image, neighboring pixels are no longer always neighbors in the serialized form. In case of the compressed string, neighboring tokens in the compressed form might contribute to distant positions in the original string.

4. That is, we can accept that the laws of nature are only descriptions, and that mathematically, a seemingly non-local description might be "natural" in some sense, of an object that is actually local.

5. The last step, which is intuitively implausible, but might be a surprise Nature has for us, is that some descriptions might be easier/more tractable/simpler/more computable in the non-local form even though they are equivalent to some description that respects locality.

6. It may even be that the really difficult part of such a non-local description is to prove that it is equivalent to a local description.

7. If we are at an impasse at finding the laws of nature (read quantum gravity) maybe this is a necessary widening of our net to uncover the laws.

Thanks for reading this far :)
-Arun

Phil Warnell said...

Hi Bee,

I couldn’t agree more that understanding what has the world to be nonlocal or seemingly nonlocal is perhaps the key to having fundamental physics move forward. I therefore also hope that the group you assemble will be wide enough to consider all the possibilities. The fact of the matter is in our current situation the relativistic extensions of QM (that is it’s field theories) take the position that from the standpoint of transmitting discernable information the world is local, that is no faster than light signalling can be realized.

The reasons for this range all the way from the world (nature) being super-deterministic, to it being in a state of quantum equilibrium (that is for the most part), which is the quantum equivalent of thermodynamic heat death. I suspect with the recent paper you wrote in regard to the former you will be raising this point and I’m hopeful that Antony Valentini might be present to remind the group of the latter. As for the positions in between, I personally don’t see any that would satisfy what’s been observed in respect to Bell’s inequality. More over what I find to be the most intriguing about these hypothesises is there have been tests (experiments) proposed for each, such that if nothing else each can be either supported or eliminated as to have them to be science.



Best,

Phil

PTMR said...

Yeah, great topic.

I find locality and related concept of causality problematic. They seem like artificial constraints imposed by our practical needs and perspective rather then properties of reality.

I think causality should be replaced by correlations which work in all directions in space and time. Time ordering as the basis for saying that A causes B, or B causes A, is observer dependent and therefore not reliable.

This relates to locality in that space-like separated events can still be correlated through events in their past.

Giotis said...

It's doubly local but not local. What is it?

Eric said...

Hi Neil,
I know your question probably wasn't addressed at me. I was hoping someone else would answer it more directly. In any case, I think it is a good question.

I think often correlation of wave functions of at least two separated particles, and also later decoherence of that state, is separate from what classical non-locality and entanglement is. For instance, many of the correlated examples of two photons separated over long distances is accomplished simply be means of using fiber optics cables for the transmission of the photons in opposite directions. What this does is insulate the two photons from the decohering effects of the environment. Without that insulation from the environment the correlated states would disappear almost immediately.

I think, and this just one man's opinion, that real, repeatable, and measurable entanglement shows up as mass. That

Eric said...

I think, and this just one man's opinion, that real, repeatable, and measurable entanglement shows up as mass.

Btw, if this was true it would mean that gravity is a by product of entanglement. Carrying this one step farther, since there is more energy released in weak decay than the sum of energy of the individual massive particles after decay, not counting photons, it would mean there is a sizable energy taken up in entanglement in the form of photons in non-locality that is the direct cause of gravity. Correspondingly there would be less gravity of the individual components after decay than the total gravity before. So I think that is the connection between electromagnetism and gravity. Gravity is a result of an electromagnetic energy deficit in the random energy surrounding us all.

Again, just my opinion. I'll shut up now :-)

Phillip Helbig said...

Who is on the non-local organizing committee?

Phillip Helbig said...

Who is on the non-local organizing committee?

Bee said...

The workshop is organized by Fotini and me.

And, since I just noticed that our friend from Pilsen couldn't help but comment, the list of registrants that appears on the website is not equal to the list of participants.

Phillip Helbig said...

OK, you two are the local organizing committe, perhaps identical to the scientific organizing committe, but who is on the non-local organizing committee? :-)

Bee said...

You could say that I am the local organizing committee and Fotini is the non-local organizing committee. That's it. How many people does one really need to organize a 3 day workshop? Best,

B.

Eric said...

I had a thought for the phenomenology of non-locality that might be the basis of a useful experiment. It might sound out-there and on the fringe but I do not think it really is.

In 1907 a Dr Duncan, see Link here did an experiment where he claimed people lost 21 grams at the moment of death. The experiments he did were not very highly engineered or repeatable so it was pretty much excused as quack science. It did not help that he and others who believed in the results attributed the loss in weight to the soul leaving the body.

But I was thinking (always a danger sign:-) ) that a rigorous experiment could now be done using modern scientific methods. That is, enclose the living being that is near death in a controlled environment where everything, including atmosphere, bodily excretions etc., are carefully weighed and measured at all times. One could presumably do a modern and up to date physics experiment where a much, much finer resolution of weight differences before and after death, if any, could
could be resolved. I would expect if there was any it would be much smaller than 21grams.

The point of the experiment would not be to weigh the soul, but to find out if there really is long range entanglement within any living tissue that contributes to the appearance of "life". I wouldn't presume one way or the other but to my knowledge, correct me anyone if I'm wrong, that a rigorous modern experiment has never been done.

It would be a scary experiment to conduct because it
would venture into areas that many people have strong
beliefs about. Nevertheless, it would be good to have it done so it could be eliminated once and for all that there might be an extra quantity of mass and energy in animated living objects that is in addition to the mass of the atoms in the individual cells. This extra energy presumably would be the energy entangling the individual complex systems of the living tissue before death and decay.