Action-at-a-distance in Sideways EPR-Bell?

[RUTA]

Huw Price is speaking tomorrow (9 Nov) at the Univ of Maryland on his recent paper, "New Slant on the EPR-Bell Experiment," co-authored with Peter Evans and Ken Wharton (arXiv: 1001.5057v3 [quant-ph] 20 Jun 2010).

In this paper, they argue that the ontological use of action-at-a-distance (AAD) to explain the standard EPR-Bell experiment (two photons each passing through one polarizer) must be defended in light of the fact that the same correlation probability exists for a single photon passing through two polarizers ("Sideways EPR-Bell") because of S, spatial and temporal symmetries. So, if one invokes AAD in EPR-Bell, then why doesn't one invoke AAD in SEPR-Bell?

Of course, no one would use AAD to account for time-like correlations with one photon! That's ridiculous! Right?

But, anyway, maybe someone already started a discussion of this paper and I missed it. If so, please point me in the right direction. If not, I'd like to start a discussion now.

 

[DrChinese]

Huw Price is speaking tomorrow (9 Nov) at the Univ of Maryland on his recent paper, "New Slant on the EPR-Bell Experiment," co-authored with Peter Evans and Ken Wharton (arXiv: 1001.5057v3 [quant-ph] 20 Jun 2010).

In this paper, they argue that the ontological use of action-at-a-distance (AAD) to explain the standard EPR-Bell experiment (two photons each passing through one polarizer) must be defended in light of the fact that the same correlation probability exists for a single photon passing through two polarizers ("Sideways EPR-Bell") because of S, spatial and temporal symmetries. So, if one invokes AAD in EPR-Bell, then why doesn't one invoke AAD in SEPR-Bell?

Of course, no one would use AAD to account for time-like correlations with one photon! That's ridiculous! Right?

But, anyway, maybe someone already started a discussion of this paper and I missed it. If so, please point me in the right direction. If not, I'd like to start a discussion now.

Here is the link itself:

http://arxiv.org/abs/1001.5057

So how did the talk go? Can you share anything? I am interested to hear your thoughts! Especially since the paper is about the role of time and time separation as opposed to action at a distance.

 

[RUTA]

Here is the link itself:

http://arxiv.org/abs/1001.5057

So how did the talk go? Can you share anything? I am interested to hear your thoughts! Especially since the paper is about the role of time and time separation as opposed to action at a distance.

The talk was more of a group discussion, so it was easy to stay involved for the entire 2 hours.

I'm in Helsinki to give a talk at the Hiley Symposium. I'll share more about Huw's talk when I get back next week. Hopefully, you guys will have said plenty in the meantime :-)

 

[DrChinese]

The talk was more of a group discussion, so it was easy to stay involved for the entire 2 hours.

I'm in Helsinki to give a talk at the Hiley Symposium. I'll share more about Huw's talk when I get back next week. Hopefully, you guys will have said plenty in the meantime :-)

Would also like to hear about the Bohm-Hiley discussions too!

 

[RUTA]

Would also like to hear about the Bohm-Hiley discussions too!

While Helsinki was not my ideal venue (I'm more a "western desert" type :-), the conference was great.

I've been wondering how the dBBers could keep their ontology in the context of their new Lorentz-invariant QFT. Turns out the field quanta (fermions and bosons) follow time-like or null paths but they don't quantize the quantum potential and it's responsible for superluminal info exchange between the field quanta, just like in QM. So, they still need a preferred frame to tell causal stories.

Met Bob Coecke and found out Danny Greenberger and Anton Zeilinger solicited the American Physical Society to form the Topical Group on Quantum Information (GQI). This group is also intended to be a representative body for quantum foundations research. This is the mission statement:

The Group is committed to serving as the home within the American
Physical Society for researchers in the foundations of quantum
mechanics. The Topical Group will promote a continuation of the
active and beneficial exchange of ideas between quantum foundations
and quantum information science.

Now I have a topical group in APS! And Bob put me on what is going to be their official mailing list.

I was surprised that our talk (Relational Blockworld) was well received, given our biases are diametrically opposed to theirs and they use algebraic methods while we use path integral. The two views can't be more different.

As for Huw's talk, I'm disappointed there isn't some conversation here about that paper, since it's very accessible and it makes some interesting arguments concerning action-at-a-distance (AAD, which I find is usually supported here). I believe there's only one equation in the entire paper -- which Huw says has been accepted by BJPS (so we should be allowed to discuss it here!). Anyway, in his talk he said, "Taking off my philosopher's hat, there's no causality in the world, there are only correlations." So, it strikes me as odd that in this paper they're working so hard to establish time-like/null beables to tell a story about backwards causation.

I asked him why they chose the paths they did for the figures (classical null), since the spacetime paths could just as well be spelling out "Huw is God" per the path integral approach (to which they appeal for their S symmetry argument). He had no answer of course, it's empirically unjustifiable.

So, Huw wants to "save the (dynamical) appearances" by employing backwards causation to avoid AAD and non-separability. But, his causal story uses empirically unaccessible beables on unjustifiable spacetime paths without temporal direction and without anything "happening" (it's a 4D picture). I don't see how one's dynamic intuition can be satisfied by this approach. And, I don't understand why someone who believes "there's no causality, there are only correlations" would bother with such a baroque ontology that yields a pseudo-causal structure, at best, when we have an ontologically parsimonious alternative that uses "only correlations." And, RBW suggests a new approach to classical gravity and, therefore, unification. For all his efforts he has nothing more than an interpretation of QM at the end of the day.

Well, maybe someone will step up in his defense :-)

 

[Price]

So, Huw wants to "save the (dynamical) appearances" by employing backwards causation to avoid AAD and non-separability. But, his causal story uses empirically unaccessible beables on unjustifiable spacetime paths without temporal direction and without anything "happening" (it's a 4D picture). I don't see how one's dynamic intuition can be satisfied by this approach. And, I don't understand why someone who believes "there's no causality, there are only correlations" would bother with such a baroque ontology that yields a pseudo-causal structure, at best, when we have an ontologically parsimonious alternative that uses "only correlations." And, RBW suggests a new approach to classical gravity and, therefore, unification. For all his efforts he has nothing more than an interpretation of QM at the end of the day.

Well, maybe someone will step up in his defense :-)

Well, perhaps I could have a go.

First, it may be helpful to point out that the disagreement here is not about the EPW paper itself. The paper simply presents three options, viz:

I. Instrumentalism
II. Retrocausal realism
III. Rejecting the symmetries.

It doesn't argue in favour of any particular option; though it does argue that if you don't like II, you should be prepared to defend either I or III. Your RBW approach does argue for option I, but -- again -- that's not a disagreement with the EPW paper.

Still, you and I do disagree in the sense that I prefer option II to RBW (or other versions of option I). Why? Mainly because I think that any interpretation which says that QM is just about correlations between observable [fill in the blank]s is going to have give a special ontological status to [fill in the blank]s -- measurement readings, observers' sensory data, classical macroscopic events, or whatever -- and that that leaves us with the measurement problem in a big way. By putting up with some unobservable ontology, we avoid having to make observability play a special role. (This kind of trade-off isn't peculiar to QM, incidentally.)

You could put it like this. We both think that QM is all about patterns of correlations in a block world. Since you don't like the idea of unobservable HVs, observability has to play a special role in your ontology -- your correlations are correlations between observations, or something like that. I don't want to privilege observation in this way, so I want some often-unobservable ontology to be what the correlations are correlations of.

You expressed surprise at my remark that there's a sense in which causality comes from us, but I've been saying it for a long time. See the middle paragraph on p. 20 in gr-qc/9406028 for example, and the development of the idea in later pages. (There is similar material in my book.)

Thanks for coming along in College Park!

 

[RUTA]

Hi Huw,

This is a joint Silberstein/Stuckey reply, let’s keep it simple, call us Silberkey or Stuckstein in keeping with our rabid monism, preferably the former. We appreciate your responding here as it gives us a chance to clear up some serious misunderstandings on your part about RBW and have you answer our questions about your ontology.

Take home message
First, we are not instrumentalists in any way, shape or form. We do not say QM is about relations between observables a la Mermin or what have you: we don’t have correlations between observations. We have an unobservable ontology as well, just not a “constructive” one in the Einsteinian sense of the word. A crude metaphor would be the “face vase illusion” where the faces represent the dynamic view of two entities in spacetime and the vase represents the adynamic relational view a la Regge calculus where both the metric and stress-energy tensor reside on the links of the graph -- it’s not matter in spacetime (faces) but a unified spacetimematter (vase). Neither observability nor measurement plays a special role in our account. We have no measurement problem of any kind; see our FoP paper (section 3.1, p. 368) for a detailed resolution of the measurement problem.

http://www.123opticalillusions.com/pages/Facevase.php

[URL]http://www.123opticalillusions.com/pages/Facevase.php[/URL]

Details
We can see why a cursory or surface reading of our work might lead you to think these things about RBW however. In order to see why they are not true it’s perhaps best to start with the root of what really divides us from you. We both agree that the blockworld (BW) should bear significantly on explanation and ontology even in QM, such as the explanation of EPR correlations. We also consequently both want to explain EPR correlations in a way that preserves locality.

However, you still (sometimes appear to) assume that the deepest explanation for such QM correlations and other QM weirdness is a dynamical one (however backwards some of the dynamics maybe) given in terms of dynamical laws governing constructive entities (however weird the entities). We have gone a totally different direction. We think that relativity and QM together are telling us that the constructive/dynamical story is not the deepest one; see our FoP and SHPMP papers plus the arXiv paper on QFT for the details, but …

Essentially, we explain QM weirdness of all sorts with an acausal global constraint rather than backwards dynamics and the like. We build the dynamic, local and separable reality of everyday (classical) physics/experience statistically from a deeper adynamic, non-separable reality; (locality per Lorentz invariance emerges at the dynamic level as explained in the arXiv paper). Accordingly, experimental QM outcomes can evidence the deeper adynamical and non-separable composition of the dynamical entities involved in the experiment (such as mirrors, beam splitters, and detectors). Exactly how the dynamic is built statistically from the adynamic is modeled by our path integral formalism over graphs (which produces a partition function a la Wick rotation in QFT). The fundamental rule for building graphs which are guaranteed to statistically produce divergence-free dynamics (whence conservation laws) is given by a constraint equation involving the difference matrix and source vector of the actional in the path integral over the graph. That constraint equation (the self-consistency criterion) is what we mean by an “acausal global constraint;” it results in a self-consistent, co-construction of space, time and matter – thus, we have non-separability at the deeper level which is guaranteed to rear its ugly head when the dynamic level is probed closely enough, i.e., in corresponding QM experiments.

Our fundamental ontology therefore is a specific instance of ontological structural realism, but we go beyond mere interpretation of the quantum. To sum up how this ontology and our formalism for modeling it lead to a new approach to quantum gravity and unification is simply that GR be replaced by a non-separable Regge calculus, and we’re working on that now. But, that will have to remain the topic of another exchange.

We keep stalking you Huw, because if anyone on the planet should be open to this possibility of fundamental explanation being adynamical/acausal, it’s you! Because of the inspiration we have drawn from your work, you are the one person we most hope to reach.

In other words, the irony is that you also agree that causation/dynamics are “perspectival” and therefore not the deepest truths about the world. You already acknowledge that your dynamical account of QM correlations is a “pseudo”-causal/dynamical story as Stuckey’s original post brings out. You invoke path integral machinery but you don’t provide an interpretation of the formalism (we do, see our arXiv paper on QFT), which of course you must if you want to proclaim yourself a realist about some beables underneath zooming around explaining observables. So we ask you, what exactly are you a realist about? What are your beables? What is the path integral formalism really about at bottom according to you?

Bottomline: either you really believe there is a truly causal/dynamical story underneath BW and QM correlations or you don’t. If the latter, as you sometimes suggest, then why do you persist in telling such pseudo just-so stories? Why not join us in looking for the deeper acausal account? If the former, as you sometimes suggest, then help us to interpret your remarks about causation being perspectival and correlations fundamental. Sometimes it seems to us that you are speaking with a forked-tongue (no pun intended, but we would like a response about Quantum Liar).

Let us give you an analogy from the Hiley-fest in Helsinki. As you know, neither Hiley nor Bohm (including some of their collaborators) is/was a realist about “Bohmian mechanics”: they are not realists about the pilot wave, particles, non-locality, etc. Hiley now has a fundamental algebraic-process oriented theory from which Bohmian mechanics emerges in the appropriate limit. We also have a fundamental theory from which the QM and the classical emerge, but unlike Hiley, ours is not a dynamical account based on algebraic-process, it’s an adynamical account with discrete path integrals over graphs constructed via a self-consistency criterion. So here at least are two clear competitors for explanations fundamental to QM, one more Heraclitean (Hiley) and one more Parmenidian (RBW). What’s your alternative? Where do you stand? In any case, we are no more instrumentalists than Hiley.

 

[Price]

Hi guys. Thanks for this long response. Thanks especially for the clarification about unobservables. I had read this -- "his causal story uses empirically unaccessible beables" -- as an expression of the view that there is something wrong with having unobservable stuff in one's ontology. (I guess that now I'm unsure how to read it.)

A couple of questions, to try to clarify things for me. What does it mean for a model to be "causal/dynamical", in your terminology? And where do you think I commit myself to such a thing? Can you find anywhere where I talk of wave functions evolving backwards (or indeed forwards) in time, for example? That sounds like dynamical talk to me, but I thought I was careful to avoid it. Nothing evolves, right? But then what is it that makes my view "dynamical"?

Naively, I had assumed that the relation between my view and RBW was like that of cats to tigers: I argue in favour of a general approach to understanding QM which might be developed in various different ways, and RBW is one of those ways (at least, if it is really not instrumentalist). If so, then our viewpoints are not in conflict, except in the sense that I am not signed up to the view that being a tiger is the best way of being a cat. But I don't think I'm signed up to the view that some rival -- a lion, say -- is a better way of being a cat. I'm neutral about that, pretty much.

Getting back to our EPW paper, I think it is important to stress that there is no commitment to any particular kind of ontology there. The whole thing is comparative and conditional: the point is that if you want some kind of local model in the Sideways EPRB case, then you should be prepared to acknowledge the possibility in EPRB, too -- unless you have an argument for breaking the symmetries.

Hope this helps.

 

[RUTA]

Hi Huw,

To begin, let us say we are perfectly happy to accept your narrative that RBW is a specific instance of a general approach to QM that you have been advocating all along and that EPW therefore doesn’t constitute a rival, conflicting theory. So from that we conclude you agree we are looking for explanation a la acausal global constraints and you take EPW to be providing just such an account. Further, you want to know why we accused you of providing a dynamical/causal account instead; part of the answer here is that we didn't know you had explicitly abandoned the backwardly causal model (BCQM), but there is more. First, by dynamical/causal explanation we generally mean things moving in space as a function of time; though of course dynamical explanation can be more abstract as in Hiley’s algebraic-process account (movement) underneath things moving in space as a function of time. Second, more specifically by dynamical/causal we mean explanations involving entities moving on time-like or null worldlines that “cause” outcomes. Your EPW paper explicitly and exclusively uses such paths for the photons “causing” the detector clicks. So our questions for you are two fold:

1) We can only understand your MOTIVATION for choosing such locality preserving paths if you are intent upon preserving a dynamical/causal story that traces paths directly from source to outcomes or the reverse. But if you have truly abandoned the necessity of dynamical/causal explanation for such QM correlations in favor of acausal global constraints, then your choice of such paths is puzzling. What are we missing?

2) The path integral formalism doesn’t JUSTIFY restricting yourself to such time-like or null paths. Indeed the paths could just as well possesses space-like pieces with EQUAL PROBABILITY according to the formalism. Again, are we missing something?

So our job now is to convince you that RBW is the best specific instance of the kind of theory you are looking for. Let’s begin with some comparisons with EPW even though it’s not a direct competitor. First, unlike your unobservable ontology (though you say EPW has no ontology), our unobservable ontology of relations is directly responsible for the observable/classical ontology and we have “theory X” showing how that is accomplished. In this context, quantum physics is simply the continuum approximation of theory X. In Regge calculus, stress-energy and the metric are both associated with links of the graph and GR is its continuous approximation, i.e., a picture of classical objects/substances in spacetime. Thus, a non-separable Regge calculus graph, i.e., every link must have stress-energy, is just the average of the graphs of our theory X and we immediately see that GR is the separable, continuous approximation to non-separable Regge calculus. Second, that means our unobservable ontology leads directly to a new suggestion for fixing the quantum gravity impasse, as well as resolving the conceptual/formal conundrums in quantum physics (both NRQM and RQFT), see the arXiv paper for all the gory details. In short, RBW isn’t just another interpretation of QM, it’s physics (a program of unification) every bit as much as CDT or LQG. RBW provides a theory fundamental to the quantum and the classical from which those emerge in their respective limits. Now we understand that RBW is formally (if not conceptually) daunting and that verifying the touted virtues of our approach is taxing and time consuming. But Huw, given your avowed perspective, we can’t understand why you wouldn’t want to see for yourself if our claims are true. We would love to take you through it all in detail until you are either satisfied or find a fatal flaw. This would take a few hours and a black/white board, but we would be honored to do it anywhere in spacetime you like.

Rather than casting shadows on EPW we would rather persuade you by illuminating RBW, so hopefully this will be our last parting shot. There is no ambiguity as to how our unobservable ontology relates to the observable/classical ontology. On the other hand, it’s not at all clear to us how your unobservable ontology (whatever it is) is responsible for or explains, i.e., is fundamental to, the observable/classical ontology in your picture. Thus, our “complaint” about unobservable beables with empirically unverifiable worldlines. And, if you’re truly punting on the necessity of causality and dynamical storytelling, why not connect space-like separated outcomes directly via space-like line segments and allow “information exchange” thereupon? That’s much simpler and doesn’t buy you anything less. Thus, it’s entirely unclear why you bother with your particular beables and worldlines.

 

[Price]

Hi guys. I suspect it would take more than a few hours and a lot of whiteboard space to get me through RBW -- like improvements to my education, many years ago (and even I don't think that that's possible to arrange, at this late stage). But thanks for the offer!

There are just two things I want to take issue with in your latest post.

First, it isn't true that I have "explicitly abandoned the backwardly causal model (BCQM)". It isn't true because I never held that view in the first place (in the sense you mean). I always meant what I mean now, which isn't "causal/dynamical" in your sense -- though it is appropriately called "retrocausal", in my view, for reasons I explain in various places (see the reference in my first post in this thread, for example).

Second, I think you are missing something important about the logic of the EPW argument. In that paper, E, W and I are not endorsing any view, in our own voice. We are simply saying to our intended audience something like this: "Whatever view you take about the explanation of the joint probabilities in the Sideways EPRB (SEPRB) experiment, you should be prepared to take the same view about the explanation of the joint probabilities in the EPRB experiment, too; unless you have an argument that the symmetries fail."

In particular, the EPW argument doesn't commit me (or us) to the view that the photons actually follow the null paths, or any paths, in SEPRB. All it commits us to is the view that if someone thinks this is the right story for SEPRB, then they should be prepared to acknowledge that it might be the right story for EPRB, too; unless they have an argument that the symmetries fail.

This is the basis for our claim in EPW that unless one has an argument that the symmetries fail, one should be prepared to concede that there is action-at-a-distance in both experiments or in neither. The first option (option I in our list) is the one we call instrumentalism, the second (option II) is what I call retrocausalism (which, to repeat, doesn't necessarily mean "causal/dynamical", in your sense). Based on Mark's remarks, I had you down for option I. Now you've convinced me it can't be that one, so I'm assuming it's II.

Does that seem right? If so, we agree, in the cat/tiger sense: I think the best solution is going to be some kind of cat, you think it's a tiger. And -- just to repeat the point -- the argument of EPW doesn't commit me to any other sort of cat. In fact, it doesn't commit me to a cat (option II) at all, but just to the view that if it is not a cat then it is I or III. (Choose your own avatars for those options. A spook and a flounder, perhaps?)

 

[RUTA]

Thanks for taking the time to clear up our misconceptions. If you would tell us precisely what constitutes "retro" and what constitutes "causal" in your "retrocausalism," we will tell you whether or not RBW falls into that category :-)

 

[Gordon Watson]

IMHO, the following responses address the OP questions in the context of EPW:

1. So, if one invokes AAD in EPR-Bell, then why doesn't one invoke AAD in SEPR-Bell?

In that I (for one) do not invoke AAD anywhere, I cannot invoke it here. Instead, I join EPW in asking the alternative question:

If you do not invoke AAD in SEPRB, then why do you invoke AAD in EPRB?

To which I would reply: Because you do not recognize the equivalence classes (ECs) common to EPRB and SEPRB (see below)

2. Of course, no one would use AAD to account for time-like correlations with one photon! That's ridiculous! Right?

Yes; it is ridiculous.

3. [The Title question] Action-at-a-distance in Sideways EPR-Bell?

No; there is no AAD.

...

Rejecting AAD, and likewise rejecting any notion of "retrocausality", I remain an advocate of EPW-II and Local realism, the very means of avoiding AAD in SEPRB:

EPW-II. The means of avoiding AAD in SEPRB extends in a natural way to EPRB, eliminating AAD (and hence its conflict with special relativity) in these cases, also. (See EPW-II http://arxiv.org/abs/1001.5057, page 3.)

In short: That natural extension arises from three neglected facts:

A: Test settings establish ECs, [.}, for beable-inputs; the notation [.} deriving from the fact that ECs are both classes and sets.

B. The beable-outputs from test devices (often termed observables; which may be beable-inputs to other test devices) are members of the corresponding input ECs; and vice-versa.

C. ECs are related by cosine-squared functions (generalizations of Malus' Law).

So a unified local realistic understanding of EPRB and SEPRB derives from the ECs (with their associated deterministic digital outputs; 0 or 1; reflect or transmit) common to both the EPRB and SEPRB settings.

To see this, let the beable-inputs to an EPW polarizing cube (set at x) be any discrete random orientation from the 4π steradians of 3-space. Then, in the reflect/transmit terminology of EPW, the beable-output ECs are [Reflected at orientation x} or [Transmitted at orientation x}. Clearly, the beable-inputs belong to the same ECs. So an infinity of possible beable-inputs reduces to just two beable-input ECs. Finally, these input and output ECs are common to EPRB and SEPRB.

Consistent application of cosine-squared functions to the orientations associated with the ECs then carries the day.

QED.

 

[DevilsAvocado]

Mirror, mirror on the wall / Who in the EPR is fairest of all?


Gentlemen, thanks for interesting thoughts and info, though please correct a layman if I’m wrong – Aren’t we forgetting something...??

Spukhafte Fernwirkung = Spooky Action at a Distance​

As far as I know, action-at-a-distance (AAD) is commonly accepted by everyone these days and no one denies that the Sun, 150 million km away, do have a strong gravitational effect on Earth. (Well, maybe JenniT & Co. in the "Deniers Club" will refute this as well, but that’s another question.)

And the "spooky stuff" is of course the "beables", or whatever, "communicating" useless "information" over http://arxiv.org/abs/0808.3316" .

The mirror is neat, and confused me at first – but is this really correct in justifying the "action symmetry" (S-symmetry)? Well, the mirror is just for "convenience", the Holy Grail in Sideways EPR-Bell (SEPRB) is of course the claim that Quantum Electrodynamics (QED) proves mathematically that space and time is symmetrical interchangeable. But is this really true??

You tell me.

I always thought that QED was compatible with Special Relativity, not refuting it?? Does SR really tell us that we are free to interchange any of the three spatial dimensions (length, width, height) with the temporal dimension (time)?? Spacetime is not 3+1, but 1+1+1+1 dimensions, perfectly equal??

How do we measure the speed of light in this case?? The speed of light is 1 nm wide and 299,792,458 m long???

Yes, in SR we do have Length contraction and Time dilation, but where is the "Spatial-Temporal-Blender"? I must have missed it completely??

Let’s be bold and say that I’m right – there is no "Spatial-Temporal-Blender" in SR – then everything gets quite easy. We do not have to choose between I II or III (quite yet). Mr. Price has first to show us that Einstein was dead wrong!

Now I’m ready for the professors to slaughter me...


P.S.
Don’t take my "critics" wrong. I very much appreciate smart people who spend their time trying to solve this enigma. Personally I think RUTA is on the right track finding a solution that incorporates QM and Relativity and gravity. I think EPRB is more about that, than the "problems" of Spooky Action at a Distance (SAD )...

Time is a very interesting "phenomena" and I’ve just watched a BBC documentary about http://en.wikipedia.org/wiki/Clive_Wearing" , a man with just 30 sec memory. After a severe brain injury, he has been living for 25 years with the repeated feeling – AHHH! Conscious at LAST! – forgetting every previous AHHH-feeling. He categorizes himself as "living dead". He can’t "think", he has no memories, just a small "window" of 30 sec "now".

If anything, this tell me that the "real" objective world that might exist "beneath" QM might be timeless or time symmetrical or whatever, but this world is not suitable for human brains... we need time to think and we need to think to find out if time exist or not...

https://www.youtube.com/watch?v=<object width="480" height="385">
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If anyone is interested in more about Clive Wearing, there’s a 1 hr web replay on http://svtplay.se/v/2223687/dokumentarfilm/mannen_med_sju_sekunders_minne?sb,p115254,4,f,-1" (English speaker) available until 4-Dec-2010.

 

[DevilsAvocado]

While Helsinki was not my ideal venue (I'm more a "western desert" type :-), the conference was great.

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[Price]

Thanks for taking the time to clear up our misconceptions. If you would tell us precisely what constitutes "retro" and what constitutes "causal" in your "retrocausalism," we will tell you whether or not RBW falls into that category :-)

I recommend my little Toy Models paper (http://arxiv.org/abs/0802.3230" ) on this point. The model in that paper illustrates in a simple way how a system of global constraints can force an experimenter to accept something like this: "If my intervention (e.g., a choice of a measurement setting) had been different, the system would have to have been different, prior to my intervention."

That's all I mean by retrocausality, so my question was whether RBW would put us in that position, as experimenters. If so, then it is retrocausal, in my sense of the word.

 

[RUTA]

As far as I know, action-at-a-distance (AAD) is commonly accepted by everyone these days

Huw's paper is aimed at this "silent majority." If they really believe in AAD for EPRB, then they have to argue why it's not their story for SEPRB. AAD in SEPRB? Even to refer to that scenario as "ERPB" is ridiculous. Right? Of course, that's what makes it such a cool paper.

And the "spooky stuff" is of course the "beables", or whatever, "communicating" useless "information" over http://arxiv.org/abs/0808.3316" .

The mirror is neat, and confused me at first – but is this really correct in justifying the "action symmetry" (S-symmetry)? Well, the mirror is just for "convenience", the Holy Grail in Sideways EPR-Bell (SEPRB) is of course the claim that Quantum Electrodynamics (QED) proves mathematically that space and time is symmetrical interchangeable. But is this really true??

You tell me.

I always thought that QED was compatible with Special Relativity, not refuting it?? Does SR really tell us that we are free to interchange any of the three spatial dimensions (length, width, height) with the temporal dimension (time)?? Spacetime is not 3+1, but 1+1+1+1 dimensions, perfectly equal??

How do we measure the speed of light in this case?? The speed of light is 1 nm wide and 299,792,458 m long???

Yes, in SR we do have Length contraction and Time dilation, but where is the "Spatial-Temporal-Blender"? I must have missed it completely??

Let’s be bold and say that I’m right – there is no "Spatial-Temporal-Blender" in SR – then everything gets quite easy. We do not have to choose between I II or III (quite yet). Mr. Price has first to show us that Einstein was dead wrong!

Now I’m ready for the professors to slaughter me...

Not to worry, the S symmetry here is not 'really' mixing space and time. The source events (particle creation and annihilation) are null related so they remain null under space-time exchange. That's the trick. But, of course, while this is a straight forward formal explanation for why the correlation probabilities in EPRB and SEPRB are the same, it's ontological implications are challenging for the conventional view; at least, so long as one's ontology respects the formalism. Thus, the point of the paper and its three options.

Don’t take my "critics" wrong. I very much appreciate smart people who spend their time trying to solve this enigma. Personally I think RUTA is on the right track finding a solution that incorporates QM and Relativity and gravity. I think EPRB is more about that, than the "problems" of Spooky Action at a Distance (SAD )...

According to Huw, RBW might be a specific version of his "retrocausalism" [the term previously known as "backwards causation?"], what he calls his option II. That's hard for me to understand, since we characterize our approach as "adynamical" and "causation" is germane to dynamism in my lexicon. We won't know whether RBW is retrocausal until he defines retrocausalism; our request for that definition was not rhetorical and I'm hopeful he provides it.

If anything, this tell me that the "real" objective world that might exist "beneath" QM might be timeless or time symmetrical or whatever, but this world is not suitable for human brains... we need time to think and we need to think to find out if time exist or not...

I'm interested in the nature of consciousness, especially given the hard problem of consciousness. As Penrose implies in some of his statements on AI, consciousness can't be modeled reductively -- since the model would be a product of consciousness. Thus, I'm leaning toward consciousness as fundamental. Thankfully, I don't have to worry about that now -- I've plenty of physics to keep me busy in the immediate future :-)

 

[Gordon Watson]

I recommend my little Toy Models paper (http://arxiv.org/abs/0802.3230" ) on this point. The model in that paper illustrates in a simple way how a system of global constraints can force an experimenter to accept something like this: "If my intervention (e.g., a choice of a measurement setting) had been different, the system would have to have been different, prior to my intervention."

That's all I mean by retrocausality, so my question was whether RBW would put us in that position, as experimenters. If so, then it is retrocausal, in my sense of the word.

Do you mean:

A: "If my intervention (e.g., a choice of a measurement setting) had been different, the system would have to have been ONTOLOGICALLY different, prior to my intervention." ?

As a convinced local-realist, I would say:

B: "If my intervention (e.g., a choice of a "measurement" setting) had been different, the system would be EPISTEMICALLY different."

This view follows from the fact that a change of test setting, say a test polarizer from orientation a to b, changes the equivalence classes ([.}) to which the (forthcoming, subsequent) outputs will belong; e.g., from [a+} XOR [a-} to [b+} XOR [b-} if the test polarizer has dichotomic (+, -) outputs.

That is what test devices do, under a change of setting.

Then, since the inputs belong to one of the output equivalence classes, the system has been EPISTEMICALLY re-classified from [a-} XOR [a-} to [b+} XOR [b-}; which is not a physical change, but a change to the type of predictions we can make. See Bohr's italicized-emphasis, in his 1935 response to EPR.

 

[Price]

Do you mean:

A: "If my intervention (e.g., a choice of a measurement setting) had been different, the system would have to have been ONTOLOGICALLY different, prior to my intervention." ?

Yes, that's what I mean. A mere epistemic difference doesn't count as retrocausality, as I use the term. Thanks for clarifying this point.

 

[ThomasT]

One of the things that I liked about the EPW paper was their position that the results of EPRB and SEPRB setups aren't just superficially similar -- though this doesn't seem to be a popular view, and I wonder if some of you might explain what's wrong or right with it in your opinions.

Wrt to my more or less pedestrian layman's view, the similarity between EPRB and SEPRB is one of the main reasons that assuming AAD seems unwarranted, to me. Without resorting to retrocausality.

Two final questions. AAD doesn't seem to me to be at odds with static or tenseless theories of time. Doesn't the block view accord with an AAD explanation of timelike as well as spacelike separated correlated events -- apparent dynamical, causal evolutions being considered as just perspectival artifacts? Might both the RBW and EPW views be considered essentially anthropocentric, instrumentalist views?

Thanks,
Tom

 

[RUTA]

One of the things that I liked about the EPW paper was their position that the results of EPRB and SEPRB setups aren't just superficially similar -- though this doesn't seem to be a popular view, and I wonder if some of you might explain what's wrong or right with it in your opinions.

That these two set ups don't differ formally is consistent with the RBW view that dynamics is "after the fact." That is, the most fundamental facts about reality reside "beneath" the classical/dynamical/causal level, and while these fundamental facts give rise to a dynamic, causal classical reality (on average), the fundamental facts are not themselves dynamic/causal. Thus, not all phenomena will conform to dynamic/causal storytelling. I've just read Huw's "Toy Models for Retrocausality" (arXiv 0802.3230, per his suggestion) and his paper provides a very nice example of this point.

In that paper, the fundamental rules don't say anything about "causation." Neither do they require a spatiotemporal context (this has to be put in "by hand," after the fact). Upon supplying a spatiotemporal context, one can tell dynamic/causal stories with some graphs. But, other graphs defy any such attempt (unless one simply perverts the meanings of dynamics and causation -- we have that response in the works).

So, in short, as John Candy says in the movie "Splash" about women appearing naked in public, "I'm for it of course."

Wrt to my more or less pedestrian layman's view, the similarity between EPRB and SEPRB is one of the main reasons that assuming AAD seems unwarranted, to me. Without resorting to retrocausality.

You can also invoke AAD by using a preferred frame as in dBB. Nothing in relativity rules out the use of a preferred frame and/or space-like worldlines. [Note: dBB might be characterized as the antipode of RBW]

Two final questions. AAD doesn't seem to me to be at odds with static or tenseless theories of time. Doesn't the block view accord with an AAD explanation of timelike as well as spacelike separated correlated events -- apparent dynamical, causal evolutions being considered as just perspectival artifacts? Might both the RBW and EPW views be considered essentially anthropocentric, instrumentalist views?

I effectively answered your first question in the affirmative immediately above. As for your second question, I will speak to RBW and let Huw respond concering EPW.

We do not consider RBW to be a form of instrumentalism, because we provide a specific model to accompany our discrete path integral formalism over graphs (Figs 1 -4 in arXiv 0908.4348). Further, our approach suggests an explicit correction to classical physics, i.e., Regge calculus be rendered non-separable so that GR is understood as the continuous, separable approximation to the "true" theory -- non-separable Regge calculus. For me (maybe other physicists, too?), such a model "is" the ontology. Silberstein often corrects me on this point. In fact, the model and formalism do not dictate any specific ontology (or any ontology at all, for that matter). So, I suppose I have to go further and link the model to experience? I'm not exactly sure what is required, but there will always be a disconnect between the mathematics and experience. As Wheeler says in the video "Creation of the Universe," about equations used to describe reality, "Write your equations on the tiles of the floor. When you're done, wave a wand over the equations tell them to fly. Not one will sprout wings and fly. The universe flies, it has a life to it that no equation has."

Neither is RBW in anyway anthropocentric -- there is nothing special about human observations per RBW. We constantly refer to "experimental outcomes" simply because that is how physics is checked. If you've ever done experimental physics, you know it's an art. That is, since physical theory is grossly simplified (by necessity), checking its predictions requires isolating that which can be modeled and this requires correcting for unavoidable influences, e.g., gravity of Moon in particle physics experiments (apparently, this effect has been observed), as well as identifying noise. So, anyway, we don't believe there is anything special about human observation other than the simple fact that humans are responsible for physics.

 

[RUTA]

I recommend my little Toy Models paper (http://arxiv.org/abs/0802.3230" ) on this point. The model in that paper illustrates in a simple way how a system of global constraints can force an experimenter to accept something like this: "If my intervention (e.g., a choice of a measurement setting) had been different, the system would have to have been different, prior to my intervention."

That's all I mean by retrocausality, so my question was whether RBW would put us in that position, as experimenters. If so, then it is retrocausal, in my sense of the word.

Hi Huw,
After reading your "Toy Models for Retrocausality" paper, which we both quite liked and found illuminating, we feel that it really illustrates the deep affinities and perhaps deep differences between us. The part of the paper that corresponds perfectly with the RBW physical/mathematical model is your toy Helsinki model. As you point out, these five rules represent adynamical/acausal global constraints (time evolution must be put in by hand) serving as an analogy for the real rules in reality that might explain, and are fundamental to, EPR correlations in a way that preserves locality. RBW, in the form of the SCC at bottom, does exactly this. However, we do not have to embed our graphs in M4 or any other spatial background because our rule (SCC) generates spacetimematter in one step as an amalgam. This is partly how we are able to unify the QM and GR in various ways.

However, in spite of your Helsinki model, as the name "retrocausality" in the title suggests, you seem to want to emphasize not the adynamical/atemporal account underneath EPR correlations, but rather the counterfactual/manipulationist patterns that exist between future and past events at the level of the phenomena itself that can be interpreted causally in the counterfactual sense by beings such as us. In other words, you seem most concerned about saving appearances rather than emphasizing what those appearances are covering up. Of course RBW acknowledges those counterfactual patterns exist and are useful for the pragmatics of explanation for beings such as ourselves, as opposed to say, Tralfamadorians; and indeed we recover ordinary classical and quantum mechanics. By contrast however, RBW is primarily concerned with explaining why those counterfactuals obtain via the adynamical rules underneath, as represented by your toy Helsinki model, as this is where the most fundamental explanation resides. In short, we would say that your "Toy Models for Retrocausality" paper buries the lead. RBW is really taking the god's eye or "Archimedean" view seriously and looking for adynamical/acausal (even in the merely counterfactual sense of causal) explanatory rules fundamental to the phenomenological patterns so chunked.

So our question to you is, are the differences between us deep or just a matter of emphasis?

Cheers,
MS&MS

 

[Gordon Watson]

One of the things that I liked about the EPW paper was their position that the results of EPRB and SEPRB setups aren't just superficially similar -- though this doesn't seem to be a popular view, and I wonder if some of you might explain what's wrong or right with it in your opinions.

1. What's right? Their challenge to AAD Orthodoxy! Their recognition of option EPW-II.

2. What's wrong? Their description of EPW-II as "Retrocausal realism" -- a cure worse than the disease -- instead of challenging aliens, they're breeding with them!

Here's what a Retrocausal-realist believes (see Price at Post #18 above): "If my intervention (e.g., a choice of a measurement setting) had been different, the system would have to have been ONTOLOGICALLY different, prior to my intervention." ?

-----------------

As a Local-realist, I believe: "If my intervention (e.g., my choice of a "measurement" setting) had been different, the system would be EPISTEMICALLY different."

[NB: EPISTEMICALLY = of or relating to knowledge or to the degree of its validation.]

This view follows from the fact that a change of test setting, say changing a test polarizer from orientation a to b, changes the equivalence classes ([.}) to which the (forthcoming, subsequent) outputs will belong; e.g., from [a+} XOR [a-} to [b+} XOR [b-} if the test polarizer has dichotomic (+, -) outputs: + indicating a response parallel to the polarizer's principal axis; - indicating an orthogonal response.

That is why we change settings -- to learn something new, in terms of ECs ...

because learning much more about sensitive HVs is impossible due to perturbative transitions during "measurement"; that is why HIDDEN VARIABLES is a good name for them; for there are "no infinitesimals by the aid of which an observation might be made without appreciable perturbation."{Heisenberg, 1930; Physical Principles} ...

so that is what test devices do, under a change of setting -- they change the observable ECs.

Then, since the HV inputs belong to one of the output (observable) equivalence classes, the system has been EPISTEMICALLY re-classified from [a-} XOR [a-} to [b+} XOR [b-}; which is not a physical change, but an epistemic change to the type of predictions we can make. See Bohr's italicized-emphasis, in his 1935 response to EPR (and see below re the lessons from relativity).

.....

IMHO, and in brief: EPW-II is nothing but Local Realism (LR). You accept LR for SEPRB? You can accept the same for EPRB.

Now --- hopefully before you stop reading --- EPW, page 6, identifies Bell's Independence Assumption -- the HVs are independent of the choice of measurement settings (MSs). I agree.

BUT here's the neglected fact: The ECs to which the HVs belong are NOT independent of the MSs. The whole purpose of "measuring" devices and their MSs is to establish the ECs under which the system "to be measured" will be classified. The system/device interaction (generally a perturbation) delivers a "measurement" result (an observable outcome) which eliminates all but one of the ECs. The outcome observable and the related system HV belong to the same EC. In EPRB and SEPRB, the ECs are related by a cosine-squared function of their respective identifiers; e.g., P([b=+} | [a+}) = cos^2 (a+, b+) = cos^2 ([B]a[/B], b); etc. [Here, P = probability, and the argument (a+, b+) denotes the angle between a+ and b+; etc.]

PS: You might follow EPW better (in so far as more easily understanding the relevant ECs) if you change gamma in Fig. 2 to alpha [for easier comparison with Fig. 1.]

...

Expanding; to show how the theory of relativity has lessons for QM:

Bell says: "Thus the result of the measurement [say a+, in my terms] does not actually tell us about some property previously possessed by the system."{Bell, 1987 p.35}

To the contrary: The test result a+ tell us which one of [a+} xor [a–} is applicable as a property previously possessed by an HV (noting especially that: to be a member of a particular EC is a property)! For without this discrimination among the available ECs, [a+} XOR [a-}, a+ would not be a relevant test result.
Here's Bell again: "While imagining that I understand the position of Einstein … as regards the EPR correlations, I have very little understanding of the position of his principal opponent, Bohr."{Bell, 1987, p.155}

But as Bohr emphasized: At the last critical stage of the test procedure, as the test setting is finalized, there is "no question of a mechanical disturbance of the system under investigation ... But ... there is a question of an influence on the very conditions which define the possible types of predictions regarding the future behavior of system;"{Bohr, 1935; EPR-reply; Bohr, 1949; Discussion with Einstein} "… closer examination reveals that the procedure of measurement has an essential influence on the conditions on which the very definition of the physical quantities in question rests;"{Bohr, 1935; in Nature} the theory of relativity "reminds us of the subjective character of all physical phenomena, a character which depends essentially upon the state of motion [upon the reference frame, in my terms] of the observer."{Bohr, 1929; Die Atomtheorie} In general terms, Bohr compares temporal relations in special relativity with properties in QM via their mutual reliance on the reference frame: "And just as the choice of a different frame of reference in relativity affects the result of a particular measurement, so also in quantum mechanics the choice of a different experimental set up has its effects on measurements, for it determines what is measurable."{Jammer, 1974; p. 201}

Wrt to my more or less pedestrian layman's view, the similarity between EPRB and SEPRB is one of the main reasons that assuming AAD seems unwarranted, to me. Without resorting to retrocausality.

A good reason. So why not add it to the better reasons: The "alternatives" [AAD and Retrocausality] being neither possible -- nor required?

 

[DevilsAvocado]

RUTA, thanks for your feedback. Sorry for late response. I’ll get back tomorrow, promise!

 

[RUTA]

1. What's right? Their challenge to AAD Orthodoxy! Their recognition of option EPW-II.

2. What's wrong? Their description of EPW-II as "Retrocausal realism" -- a cure worse than the disease -- instead of challenging aliens, they're breeding with them!

Here's what a Retrocausal-realist believes (see Price at Post #18 above): "If my intervention (e.g., a choice of a measurement setting) had been different, the system would have to have been ONTOLOGICALLY different, prior to my intervention." ?

I share the sentiment that something is "wrong" with retrocausality -- the retro part is clear, but where I cringe is with their use of the word "causal." The reason it strikes me as a "perverted" use of the word "causal" is because the "change" they talk about between cause and effect takes place in "pseudo-time," i.e., wrt the sequence of computation steps (this is also true of TI as Maudlin notes). For example, the last sentence of section 3 in Huw's "Toy Models" paper is,

"What we are looking for is a case in which a change in the left or right-hand input variables requires a change in the hidden state."

Now he italicizes the word "requires," which I infer means we could replace it with "causes," but the word that stands out to me is "change." Nothing "changes" in 4D, nothing happens. As best as I can tell, the "changes" in the Helsinki model refer to the computational procedure -- someone wrote A on a leg and had to change it to B when someone else decided to write C at their node. But, the process of constructing the graph has nothing to do with time in the 4D graph. That's why I would prefer the use of a term like "pseudo-causation."

Apparently, though, my notion that causation requires strict adherence to time in 4D reality is parochial. Silberstein informs me that Huw's use of the word -- "cause" in a counterfactual sense -- is widely accepted. So, I just have to live with it

The difference between EPW and RBW, as Silberstein points out in our response, is their focus on causation (in any form) when the fundamental rules are adynamical. For us, the ultimate explanation resides in the most fundamental rules, so why jump through hoops to get causal stories in graphs constructed per the Helsinki model? Accept that reality is fundamentally adynamical and see where THAT takes you. That's exactly what we do in RBW and it's suggesting a very specific correction to GR. What do you get for constructing retrocausal stories "after the fact?"

 

[DevilsAvocado]

Huw's paper is aimed at this "silent majority." If they really believe in AAD for EPRB, then they have to argue why it's not their story for SEPRB. AAD in SEPRB? Even to refer to that scenario as "ERPB" is ridiculous. Right?

I’m with you there!

Of course, that's what makes it such a cool paper.

Trying real hard...

Not to worry, the S symmetry here is not 'really' mixing space and time. The source events (particle creation and annihilation) are null related so they remain null under space-time exchange. That's the trick.

...but even more confused...

We are simply saying to our intended audience something like this: "Whatever view you take about the explanation of the joint probabilities in the Sideways EPRB (SEPRB) experiment, you should be prepared to take the same view about the explanation of the joint probabilities in the EPRB experiment, too; unless you have an argument that the symmetries fail."

In particular, the EPW argument doesn't commit me (or us) to the view that the photons actually follow the null paths, or any paths, in SEPRB. All it commits us to is the view that if someone thinks this is the right story for SEPRB, then they should be prepared to acknowledge that it might be the right story for EPRB, too; unless they have an argument that the symmetries fail.

Without the "null paths" the symmetries must fail, right?? Furthermore, which law enforces us to apply the same story to EPRB as SEPRB? We know that in SEPRB the "polarization state" has the possibility to travel from C -> B at the speed of light. This is not the case in EPRB. It could be anything; NLHV, beables, "little green men", etc. But it could not be information at the speed of light. This is where the symmetries fail, if you ask me.

(And, If we accept Retrocausality, we must maybe also accept "Precausality"? The whole universe is predestinated in Superdeterminism = End of all Discussions! )

I'm interested in the nature of consciousness, especially given the hard problem of consciousness. As Penrose implies in some of his statements on AI, consciousness can't be modeled reductively -- since the model would be a product of consciousness. Thus, I'm leaning toward consciousness as fundamental.

Agree, yet sometimes I suspect that our consciousness MIGHT be "accomplice" in the paradox of EPRB... Brains & consciousness need space & time to function, but EPRB & Hilbert space might do without...

 

[Gordon Watson]

I share the sentiment that something is "wrong" with retrocausality -- the retro part is clear, but where I cringe is with their use of the word "causal." The reason it strikes me as a "perverted" use of the word "causal" is because the "change" they talk about between cause and effect takes place in "pseudo-time," i.e., wrt the sequence of computation steps (this is also true of TI as Maudlin notes). For example, the last sentence of section 3 in Huw's "Toy Models" paper is,

"What we are looking for is a case in which a change in the left or right-hand input variables requires a change in the hidden state."

Now he italicizes the word "requires," which I infer means we could replace it with "causes," but the word that stands out to me is "change." Nothing "changes" in 4D, nothing happens. As best as I can tell, the "changes" in the Helsinki model refer to the computational procedure -- someone wrote A on a leg and had to change it to B when someone else decided to write C at their node. But, the process of constructing the graph has nothing to do with time in the 4D graph. That's why I would prefer the use of a term like "pseudo-causation."

Apparently, though, my notion that causation requires strict adherence to time in 4D reality is parochial. Silberstein informs me that Huw's use of the word -- "cause" in a counterfactual sense -- is widely accepted. So, I just have to live with it

The difference between EPW and RBW, as Silberstein points out in our response, is their focus on causation (in any form) when the fundamental rules are adynamical. For us, the ultimate explanation resides in the most fundamental rules, so why jump through hoops to get causal stories in graphs constructed per the Helsinki model? Accept that reality is fundamentally adynamical and see where THAT takes you. That's exactly what we do in RBW and it's suggesting a very specific correction to GR. What do you get for constructing retrocausal stories "after the fact?" [emphasis added]

Answer: AAAD in negative time; plus a headache!

NOW: While the wrestle over the meaning of words is important, I'm more at home wrestling with clear facts. As I've written above, we should forget the (very misleading) name allocated to EPW-II and deal with its challenge and facts.

To that end I ask you, price, etc. to consider this third system [which might be called Figure 1a when EPW is rewritten in response to my challenge to AAD Orthodoxy, RBW and Retrocausality: in response to my advocacy for local realism! ] I ask that you derive its correlations and discuss them in the context of your own belief system.

Figure 1a, COMPREHENDING EPRB (CEPRB -- pronounced See-perb): We take EPW's Figure 1 and sandwich the two-photon decay at M between two aligned and rigidly connected dichotomic polarizers which rotate (step-wise, in unison; but randomly) about the line-of-flight axis. The new "source", thus created, delivers photons with identical linear polarizations (orientation unknown; so true hidden-variables).

As a local realist, and an advocate of EPW-II, the new correlations follow readily, with easy understanding, and in full accord with local realism. Note that understanding of EPRB does follow from CEPRB: the name is well-intentioned and serious.

HOW does it go without local realism?

Question: Do some in RBW maintain that nothing passes from the source to the detectors?

 

[RUTA]

Question: Do some in RBW maintain that nothing passes from the source to the detectors?

In RBW there are no quantum/screened-off systems moving through the experimental equipment -- there is just the experimental equipment.

 

[DevilsAvocado]

HOW does it go without local realism?

Just fine thank you, since dinosaurs and local realism are considered extinct by most, this is not a problem worth discussing. It’s as intelligent as starting a crusade to "enlighten" the world that there is proof showing that the dinosaurs farting is causing global warming.

 

[Gordon Watson]

In RBW there are no quantum/screened-off systems moving through the experimental equipment -- there is just the experimental equipment.

OK; thank you. But, help please:

Q1: What leads to Red (R) and Green (G) lights blinking on the test devices?

Q2: Why do these G/R blinkings correlate with my pressing a button on the source; as well as with each other?

Q3: Why do my hands get warmer as I hold them between the source and the test devices while someone else presses the button?

Q4: Why do photographic plates show point-like exposures when held between the source and the test devices while someone else presses the button?

Q5: Will your answers equally apply to CEPRB, which is wholly classical?

With thanks again, might I suggest that there are related questions, answers to which would help many of us understand RBW?

PS: Is there an RBW FAQ on the web?

 

[RUTA]

Without the "null paths" the symmetries must fail, right??

Well, it's not really null "paths," it's null-related sources (creation and annihilation of field excitations/particles). When you do the path integral between these sources, you'll take into account all types of paths.

Furthermore, which law enforces us to apply the same story to EPRB as SEPRB?

Their argument is simply against telling different ontological stories in EPRB and SEPRB. There are typically two different ontological stories about these two experiments, but the formalism doesn't support such a difference.

We know that in SEPRB the "polarization state" has the possibility to travel from C -> B at the speed of light. This is not the case in EPRB. It could be anything; NLHV, beables, "little green men", etc. But it could not be information at the speed of light. This is where the symmetries fail, if you ask me.

The formalism for the null-related sources in these two experimental configurations is the same per S symmetry. So, why aren't the standard ontological accounts the same?

While that's all they're saying, it's a pretty surprising challenge. That's why I think it's a cool paper. And the discussion here led me to read Huw's "Toy Models" paper and opened a window into what he means by "retrocausality."

 

[Gordon Watson]

Just fine thank you, since dinosaurs and local realism are considered extinct by most, this is not a problem worth discussing. It’s as intelligent as starting a crusade to "enlighten" the world that there is proof showing that the dinosaurs farting is causing global warming.

Are dinosaurs extinct in RBW?

Indeed: You seem to prove that they are not?

 

[Gordon Watson]

In RBW there are no quantum/screened-off systems moving through the experimental equipment -- there is just the experimental equipment.

RUTA, please excuse my continuing puzzlement, but: Which experimental equipment would that be?

The two with Green lights? The two with Red lights? The two with neither? Plus combinations of same?

How does RBW account for the dynamic phenomena?

Are you saying that nothing moves from the equipment to my eye to convey these dynamics?

Thank you.

 

[DevilsAvocado]

Are dinosaurs extinct in RBW?

It’s safest if RUTA answers any questions about RBW. My guess though, is that dinosaurs definitely are extinct in RBW. If there are any creatures looking like dinosaurs, it’s a completely new breed called spacetimematterdinosaurs...

Anyhow, if your hope is that RBW is saving the holy Local Realism for you, I’m afraid you’re going to get heavily disappointed. RUTA and his partners are trying to break new (extremely difficult) ground, not refuting accepted standards in the scientific community.

PS: Is there an RBW FAQ on the web?

http://arxiv.org/find/quant-ph/1/au:+Stuckey_W/0/1/0/all/0/1"

I think your questions about devices and measurement is answered by this picture:

(RUTA, if there’s any error, my apologies in advance.)

 

[DevilsAvocado]

Well, it's not really null "paths," it's null-related sources (creation and annihilation of field excitations/particles). When you do the path integral between these sources, you'll take into account all types of paths.

Their argument is simply against telling different ontological stories in EPRB and SEPRB. There are typically two different ontological stories about these two experiments, but the formalism doesn't support such a difference.

The formalism for the null-related sources in these two experimental configurations is the same per S symmetry. So, why aren't the standard ontological accounts the same?

While that's all they're saying, it's a pretty surprising challenge. That's why I think it's a cool paper. And the discussion here led me to read Huw's "Toy Models" paper and opened a window into what he means by "retrocausality."

Thanks a lot for the feedback.

I’ve been tweaking my "CPU" to max, to see if anything comes out in the "Arithmetic Logic Unit". And the result is almost embarrassing ().

I’ve localized the problem – it’s "lost in translation" related... It’s the two words ontology and formalism, which messes up things for me. Please correct me if I’m wrong:

Ontology: the philosophical study of the nature of being, existence or reality as such, as well as the basic categories of being and their relations.

Meaning that, this is the way we as human beings perceive the world around us. We see the laser beam, and the polarizer, and the measuring electronics, and the clock. Now, if our consciousness is in anyway "involved" in the outcome of EPR-Bell experiments, we’re going to have a darned hard time solving this enigma, by just using the reality as we perceive it.


Formalism: describes an emphasis on form over content or meaning, and mathematics is no more than the symbols written down by the mathematician, which is based on logic and a few elementary rules alone.

Meaning that, we can write a computer program called the Game of Life, having a 2D grid of square cells and just 4 basic rules for survival. The name of the game doesn’t necessary mean it’s related to reality and the real life of living beings. The game and the rules is all there is, and we are able to do scientific research using axioms and theorems, viable in the current formalism.

The Game of Life
[PLAIN]http://upload.wikimedia.org/wikipedia/commons/e/e6/Conways_game_of_life_breeder_animation.gif[/INDENT]

I interpret the above and EPW as – Mathematically there is S symmetry between EPRB & SEPRB. In the real world with measuring apparatus, the S symmetry is broken.

Then the question remains, what is correct, mathematics or our senses and consciousness?

I have no idea... but I suspect that the "ordinary-life-of-a-brain" would never have discovered QM or Spacetime curvature, without formalism and mathematics...

Correct...??​

 

[Gordon Watson]

It’s safest if RUTA answers any questions about RBW. My guess though, is that dinosaurs definitely are extinct in RBW. If there are any creatures looking like dinosaurs, it’s a completely new breed called spacetimematterdinosaurs...

Anyhow, if your hope is that RBW is saving the holy Local Realism for you, I’m afraid you’re going to get heavily disappointed. RUTA and his partners are trying to break new (extremely difficult) ground, not refuting accepted standards in the scientific community.

<CUT>

Many many thanks, DA; could be there's one less dinosaur than many of us imagined, RBW notwithstanding. Keep it up! XXOO.

 

[DevilsAvocado]

You’re welcome JT.

 

[Maui]

Are dinosaurs extinct in RBW?

Indeed: You seem to prove that they are not?

How would dinosaurs go extinct in a universe in which time does not(is not supposed to) flow? You would need a completely new blockworld universe.

 

[Maui]

OK; thank you. But, help please:

Q1: What leads to Red (R) and Green (G) lights blinking on the test devices?

Q2: Why do these G/R blinkings correlate with my pressing a button on the source; as well as with each other?

Q3: Why do my hands get warmer as I hold them between the source and the test devices while someone else presses the button?

Q4: Why do photographic plates show point-like exposures when held between the source and the test devices while someone else presses the button?

Q5: Will your answers equally apply to CEPRB, which is wholly classical?

With thanks again, might I suggest that there are related questions, answers to which would help many of us understand RBW?

PS: Is there an RBW FAQ on the web?

Would that be very different to the "coincidence" which forced low entropy at the BB, which appears to have fined tuned the fundamental constants or answers the question why there is something instead of nothing?

How would you like to call it? Underlying reality? HV? ...?

 

[RUTA]

RUTA, please excuse my continuing puzzlement, but: Which experimental equipment would that be?

The two with Green lights? The two with Red lights? The two with neither? Plus combinations of same?

How does RBW account for the dynamic phenomena?

Are you saying that nothing moves from the equipment to my eye to convey these dynamics?

Thank you.

I was logging on to respond to your last post. I'll respond to this post and see if that helps ... it's shorter

The red and green lights are code for the relative locations of detector clicks. The pieces of equipment in this case would be the Source of silver atoms (or spin 1/2 particles), the magnet, the detector (see the picture on Wikipedia under Stern Gerlach Experiment, for example).

In an interferometer, the pieces of equipment would be the Source of particles, the beam splitters, the mirrors, the detectors (all these things would be "sources" in QFT, that's why I use "Source" to distinguish this form of "source" from a "sink"). To see how this experiment is modeled via spacetime symmetries (rather than "screened-off" quantum systems moving through the interferometer), see A. Bohr & O. Ulfbeck, Rev. Mod. Phys. 67, 1-35 (1995), or our presentation thereof in Stuckey, W.M., Silberstein, M., Cifone, M.: Reconciling spacetime and the quantum: Relational Blockworld and the quantum liar paradox. Foundations of Physics 38(4), 348-383 (2008), quant-ph/0510090.

In RBW, dynamic phenomena only appear statistically, i.e., at what is generally called the "classical level." At the most fundamental level, the "rule" is not dynamic -- like Huw's Helsinki model -- it's a criterion for building graphs. If you follow the "self consistency criterion" for building graphs at the fundamental level, then you get a partition function for the distribution of relations comprising the experiment, so you recover classical physics as a statistical limit. So, per RBW, when one is doing a "quantum" experiment, one is probing the most fundamental composition, i.e., relations, of the experimental equipment (again, there isn't any"thing" moving through the equipment). See Fig 1-4 of 0908.4348 (under review at FoP).

To answer your last question, photons are not "things," since there is no context when they're not "screened off." So, yes, no"thing" moves from the equipment to your eyes in order for you to see the equipment -- there are just relations that co-define you and the equipment. This is not a new idea, here are a couple quotes along the same lines:

"Photons are clicks in photon detectors" -- attributed to Zeilinger, arXiv quant-ph/0505187v4

"The droplets in the cloud chamber form a track that vividly conveys the image of a particle passing through the chamber, but this imagined thing is a phantasm. There are no things beyond the droplets." Aage Bohr, Ben R. Mottelson & Ole Ulfbeck, Foundations of Physics, Vol. 34, No. 3, March 2004.

 

[RUTA]

I’ve localized the problem – it’s "lost in translation" related... It’s the two words ontology and formalism, which messes up things for me. Please correct me if I’m wrong:

Ontology: the philosophical study of the nature of being, existence or reality as such, as well as the basic categories of being and their relations.

Meaning that, this is the way we as human beings perceive the world around us. We see the laser beam, and the polarizer, and the measuring electronics, and the clock. Now, if our consciousness is in anyway "involved" in the outcome of EPR-Bell experiments, we’re going to have a darned hard time solving this enigma, by just using the reality as we perceive it.​

I have very naive, parochial definitions for philosophical terms (pretty typical of physicists), but I would say something doesn't have to be "perceived" to possesses ontological status, e.g., atoms, bacteria, and viruses, are generally ascribed ontic status even though we can't directly perceive them.

Formalism: describes an emphasis on form over content or meaning, and mathematics is no more than the symbols written down by the mathematician, which is based on logic and a few elementary rules alone.

Meaning that, we can write a computer program called the Game of Life, having a 2D grid of square cells and just 4 basic rules for survival. The name of the game doesn’t necessary mean it’s related to reality and the real life of living beings. The game and the rules is all there is, and we are able to do scientific research using axioms and theorems, viable in the current formalism.

When I say "formalism" I mean the mathematical formalism of the physics, which must correspond to reality (per experiment) by definition. Your example isn't "physics," per my definition, but it "looks like" or "mimics" experience, so one might be tempted to explore it as physics, i.e., establish a corresponding experimental program.

I interpret the above and EPW as – Mathematically there is S symmetry between EPRB & SEPRB. In the real world with measuring apparatus, the S symmetry is broken.

Then the question remains, what is correct, mathematics or our senses and consciousness?

I have no idea... but I suspect that the "ordinary-life-of-a-brain" would never have discovered QM or Spacetime curvature, without formalism and mathematics...

Correct...??

I wouldn't use the term "broken symmetry" in EPW, but maybe there is some sense in which it's applicable.

Generally, we favor the experimental evidence over the theoretical predictions, but that doesn't always prove a good discriminator, e.g., Einstein didn't believe GR's prediction of the expansion of universe because it didn't match the astronomical observations of the time. Personally, I would not reject experimental data, although I would consider rejecting the analysis of experimental data. In other words, I might advocate a different analysis using the raw data, but I would not attack the raw data itself unless I (or someone I trusted) replicated the experiment and obtained different raw data altogether.​

 

[Gordon Watson]

Would that be very different to the "coincidence" which forced low entropy at the BB, which appears to have fined tuned the fundamental constants or answers the question why there is something instead of nothing?

How would you like to call it? Underlying reality? HV? ...?

I believe that:

1. Einstein was a proponent of hidden variables (HVs).

2. d'Espagnat referred to "veiled reality".

3. Bell hoped for a simple constructive model of reality.

4. I am as a beginner in their camp.

5. Bell was wrong to assert that the values of sensitive HVs are revealed by observation. It is their equivalence classes that are revealed.

6. The values of sensitive HVs remain hidden; that's why "hidden variables" is good nomenclature.

 

[DevilsAvocado]

... To answer your last question, photons are not "things," since there is no context when they're not "screened off." So, yes, no"thing" moves from the equipment to your eyes in order for you to see the equipment -- there are just relations that co-define you and the equipment. This is not a new idea, here are a couple quotes along the same lines:

"Photons are clicks in photon detectors" -- attributed to Zeilinger, arXiv quant-ph/0505187v4

"The droplets in the cloud chamber form a track that vividly conveys the image of a particle passing through the chamber, but this imagined thing is a phantasm. There are no things beyond the droplets." Aage Bohr, Ben R. Mottelson & Ole Ulfbeck, Foundations of Physics, Vol. 34, No. 3, March 2004.

This is interesting. Albert Einstein stated shortly before he died:

"Nowadays every Tom, Dick and Harry thinks he knows what a photon is, but he is mistaken".​

...

 

[DevilsAvocado]

... atoms ... are generally ascribed ontic status even though we can't directly perceive them.

This is what excite me and almost drives me crazy at the same time!

Atoms have a status of real or factual existence. And we can see them thru scanning tunneling microscope!

The positions of the individual Gold atoms
composing the surface are visible.

BUT! Atoms could not be atoms without the "imaginary" components electrons and photons (and quarks)!? The real needs the "unreal" to become existent??

It drives me nuts...

When I say "formalism" I mean the mathematical formalism of the physics, which must correspond to reality (per experiment) by definition.

I knew I missed something very important, again!

Thanks for explaining. Though, there are 4 words that (probably) brings me back to square one; "must correspond to reality".

If the formalism of EPRB & SEPRB "must correspond to reality", I cannot for my life see how the shared S symmetry could survive. There is an option for "something" to travel from C -> B at the speed of light, but this option is not available at A -> B, in the corresponding reality (sorry for repeating myself).

The only way out of this afaict, is that the "state" between the source and polarizer is "unknown" and "open" for mathematical symmetry in QED...

But I still have problems when things "pop out" into a corresponding reality... click...

Generally, we favor the experimental evidence over the theoretical predictions, but that doesn't always prove a good discriminator, e.g., Einstein didn't believe GR's prediction of the expansion of universe because it didn't match the astronomical observations of the time. Personally, I would not reject experimental data, although I would consider rejecting the analysis of experimental data. In other words, I might advocate a different analysis using the raw data, but I would not attack the raw data itself unless I (or someone I trusted) replicated the experiment and obtained different raw data altogether.

That would be my definition of an excellent scientist!

(Contrary to some shocking examples we seen discussing EPR in other threads... )

 

[RUTA]

How would dinosaurs go extinct in a universe in which time does not(is not supposed to) flow? You would need a completely new blockworld universe.

You can tell dynamical stories with a blockworld, but the 4D perspective is nicely described by this Geroch quote:

There is no dynamics within space-time itself: nothing ever moves therein; nothing happens; nothing changes. In particular, one does not think of particles as moving through space-time, or as following along their world-lines. Rather, particles are just in space-time, once and for all, and the world-line represents, all at once, the complete life history of the particle.

Geroch, R.: General Relativity from A to B. University of Chicago Press, Chicago (1978), pp 20-21.

If you're open to the 4D perspective, then adynamical approaches to physics are not so shocking. This is what Huw suggests in his "Toy Models" paper and what we're claiming in RBW, i.e., the fundamental rule of physics concerns "4D patterns" rather than dynamics.

 

[RUTA]

Atoms have a status of real or factual existence. And we can see them thru scanning tunneling microscope!

BUT! Atoms could not be atoms without the "imaginary" components electrons and photons (and quarks)!? The real needs the "unreal" to become existent??

This confusion is always generated by statements like "atoms and photons don't exist." Zeilinger has created interference patterns with large molecules (buckyballs, I think) and there's nothing in QM that says you can't get interference patterns using even bigger objects. So, do molecules not exist? Where is the "cut off?"

The "picture of atoms" you showed was generated by millions of photons per second. The belief is that the atoms are "there" whether we excite them or not. That's the source of the confusion. In the RBW "relational" view, or Bohr et al's "symmetry" view, or Zeilinger's "measurement" view, if you strip away the relations/symmetries/measurements, you lose everything. In the atomic view, you still have the atom "sitting there in space," it's just not interacting with anything, i.e., it's "screened off." Once you decide to construct "things," like the atoms in your picture, from relations/symmetries/measurements, rather than smaller "things," e.g., quarks and electrons, then you understand clearly that the atoms in your picture slowly disappear as you gradually reduce the number of relations/symmetries/measurements ("photons" in the language of "things") used to "see them." In other words, the relations (aka "photons" in "things" talk) don't allow you to "see the atoms," the relations "construct the atoms." So, given millions of photons per second, you're well into the classical regime, thus your "picture." This view makes it clear how the dynamical/causal classical reality of interacting "things" might obtain statistically from a more fundamental, adynamical reality of relations/symmetries/measurements (a la the Figure from our arXiv paper you posted earlier).

BTW, thanks for that post. I haven't had time to answer all the questions posted here for me, so I was glad you helped me out The answer was good.

 

[DevilsAvocado]

The "picture of atoms" you showed was generated by millions of photons per second. The belief is that the atoms are "there" whether we excite them or not. That's the source of the confusion. In the RBW "relational" view, or Bohr et al's "symmetry" view, or Zeilinger's "measurement" view, if you strip away the relations/symmetries/measurements, you lose everything. In the atomic view, you still have the atom "sitting there in space," it's just not interacting with anything, i.e., it's "screened off." Once you decide to construct "things," like the atoms in your picture, from relations/symmetries/measurements, rather than smaller "things," e.g., quarks and electrons, then you understand clearly that the atoms in your picture slowly disappear as you gradually reduce the number of relations/symmetries/measurements ("photons" in the language of "things") used to "see them." In other words, the relations (aka "photons" in "things" talk) don't allow you to "see the atoms," the relations "construct the atoms." So, given millions of photons per second, you're well into the classical regime, thus your "picture." This view makes it clear how the dynamical/causal classical reality of interacting "things" might obtain statistically from a more fundamental, adynamical reality of relations/symmetries/measurements (a la the Figure from our arXiv paper you posted earlier).

YES! FINALLY! I THINK I’VE GOT IT! Many many many thanks RUTA!

It’s just sweet when the brain "clicks"! This is how it must be: To make an observation of QM objects, we must "bombard" it massively on the microscopic scale, so massively that we "transcend" to the macroscopic scale. It’s almost (in the macroscopic world) like we were forced to put "heavy fire" on a building to be able to observe it (and destroying the finer "stucco properties" at the same time ). Right?

Now something else strikes me... about good old Einstein:

"Do you really think the moon isn't there if you aren't looking at it?"​

I’m not the man to settle this question, but, in respect of what you just explained – it’s not "the moon" we are looking at, it’s trillions of photons, emitted from the Sun, reflected from the surface of the Moon, finally hitting our retina, to form a picture of the macroscopic object "the moon" in our brain.

Of course, one could build a "private rocket", and put a blindfold on, and smash ones forehead into the surface of the Moon, to exclude the photons in a slightly more "brutal observation"...

Never the less, this "observation" would "transcend" to the "macroscopic heavy fire" level as well!

(and the "rocket option" is of course not available for atoms)

This is just so interesting! I think I’ve learned something very important today, in the "screen-off-business"! Thanks again RUTA!

BTW, thanks for that post. I haven't had time to answer all the questions posted here for me, so I was glad you helped me out The answer was good.

It’s my pleasure if I can help in any way (not just ask "confused" questions )! Glad it was accurate!

 

[Maui]

YES! FINALLY! I THINK I’VE GOT IT! Many many many thanks RUTA!

It’s just sweet when the brain "clicks"! This is how it must be: To make an observation of QM objects, we must "bombard" it massively on the microscopic scale, so massively that we "transcend" to the macroscopic scale. It’s almost (in the macroscopic world) like we were forced to put "heavy fire" on a building to be able to observe it (and destroying the finer "stucco properties" at the same time ). Right?

Yes. The most consistent picture is that solid matter is the result of billions of 'measurements' per second, not of solid objects existing in spacetime.

You can tell dynamical stories with a blockworld, but the 4D perspective is nicely described by this Geroch quote:

There is no dynamics within space-time itself: nothing ever moves therein; nothing happens; nothing changes. In particular, one does not think of particles as moving through space-time, or as following along their world-lines. Rather, particles are just in space-time, once and for all, and the world-line represents, all at once, the complete life history of the particle.

Geroch, R.: General Relativity from A to B. University of Chicago Press, Chicago (1978), pp 20-21.

If you're open to the 4D perspective, then adynamical approaches to physics are not so shocking. This is what Huw suggests in his "Toy Models" paper and what we're claiming in RBW, i.e., the fundamental rule of physics concerns "4D patterns" rather than dynamics.

The worldline 'moves' through successive measurements. I find that more consistent and easier on the brain than objects that disappear and reappear at the next Planck length(?) through a seemingly continuous motion. Zeno was a remarkable guy.

Is RBW completely deterministic?

 

[DevilsAvocado]

Yes. The most consistent picture is that solid matter is the result of billions of 'measurements' per second, not of solid objects existing in spacetime.

Yes this seems to be the case! (Except maybe for my "private-rocket-forehead-measurement"... )

 

[DevilsAvocado]

Is RBW completely deterministic?

... wonders too ...

RBW = Superdeterminism = No free will ...?

 

[RUTA]

"Is the Moon there when nobody looks?"

I would answer this question by first clarifying the phrase "nobody looks." If by this you mean simply "it doesn't interact with anything," then the answer is no, the Moon is not "there" when it's not interacting with anything (nothing special about interacting with humans). The Moon is not anywhere in this case -- it doesn't exist because it is defined by interactions. No interactions, no Moon. [We prefer the word "relations" to "interactions," because the latter is too dynamical; in RBW the fundamental law deals with links on graphs, and not all links correspond to "interactions." But, speaking in terms of interactions is a helpful first step.]

"The most consistent picture is that solid matter is the result of billions of 'measurements' per second, not of solid objects existing in spacetime."

Replace "solid objects" with "classical objects" and this is essentially what we're saying in RBW. I don't want to quibble, I just want to avoid confusion. There are small "classical objects," e.g., bacteria, viruses, etc., that some people might not think of as "solid objects."