"Foundations" argument: Silberstein et al engage Hiley-channeling-Bohm

bohm2

But if it's not a physical object and just a calculation, how does one explain quantum interference?

I thought I'd post this other paper on RBW that may be useful for trying to make sense of this model:

Reversing the arrow of explanation in the Relational Blockworld: Why temporal becoming, the dynamical brain and the external world are all "in the mind"
http://philsci-archive.pitt.edu/3249/1/ZiF_05_stu.pdf

zonde

But turning 3D dynamical world into 4D static blockworld does not change physical laws.
Instead of moving billiard balls we have spaghetti like objects extending in timelike directions (so obviously timelike directions differ from spacelike direction in 4D blockworld).

So we see as "normal" patterns those that are extending in timelike directions and (rather very limited) patterns extending in spacelike directions can emerge only as secondary patterns from timelike ones. And then "uncaused" events are just as strange in 4D blockworld as they are in 3D dynamical world.

Then we have this statement that relations are more fundamental than 'things'. Fine, but to claim that it makes some difference (in a consistent way) we would like to compare it with more classical approach by converting these patterns of relations into 3D dynamical representation. Or alternatively we can convert 3D dynamical laws into 4D static patterns. But it seems to me that mathematically there is no big difference between two representations and the only difference is how you visualize it.

So my question is what is this brand new thing about RBW? I don't see it.

RUTA

In current thinking, the billiard balls are made of molecules (with spagetti-like worldlines) and the molecules of atoms (again, with worldlines), etc. In fact, what particle detectors do in part is find the worldlines of fundamental particles, then the curve fitting parameters yield particle properties such as mass and charge. In RBW, the fundamental constituents are relations, not particles with worldlines, so the fundamental rule is not a dynamical law about particles (as it is with particle physics via interacting fields). The entire enterprise is thus different, we must find this fundamental adynamical rule for relations that does result statistically in dynamical laws for things with worldlines.

Here is a good way to understand how this difference is manifested conceptually in an experimental situation. In current thinking, the experimental outcome of a high-energy particle experiment includes particle tracks in the detector. The actual data is thousands of individual detector clicks so that the particle tracks are constructed by curve fitting through detector clicks. The particles/curves are then the fundamental entities according to the theory. In RBW, the individual clicks are fundamental -- or more precisely, they represent individual relations which are fundamental. See how this changes the game dramatically?

Anyway, the FoP paper just accepted (topic of thread) explains our new approach to fundamental physics. A self-consistency criterion (SCC, Kv = J) governs the construct of graphs whence transition amplitudes for various processes (K and J are constructed from boundary operators on the graph, v is the vector of vertices). As an analogy, think Regge calculus (graphical version of GR), where one uses the resulting graph to compute transition amplitudes. The paper shows how the proposed SCC (which follows from the boundary of a boundary principle, dd = 0, as do GR and EM) necessarily yields gauge invariance (and, therefore, gauge fixing) and divergence-free sources, and how it yields the 'spagetti-like world' statistically.

The paper also uses this idea to resolve QM mysteries. I'll let you read the paper, but hopefully it will be clear that we are proposing a very different way to 'explain' reality.

RUTA

Let me add an example of 4D thinking to my explanation above. In Regge calculus, one is to find the metric g and stress-energy tensor T on every link of the graph that solve Regge's equations (obtained from extremum of grahical action). So, if someone asked, "Why is there 5 kg*m/s of momentum on link X?" the answer would be, "Because that is what results from the values of T and g on link X and those values are needed to satisfy Regge's equations everywhere else on the graph. If you changed T and g on X, you would have to change them on link Y and Z and ... . Then you would have a different solution." Do you see how this differs from a (3+1)D explanation involving the history of force on some particle?

zonde

Laws for things with worldlines are not dynamical. They do not change with time.

Well, I suppose that the first thing you have to explain is - what are "relations" in RBW?

Just declaring that "relations" are more fundamental than "particles" ... it's hardly something. What we want from theory are reusable descriptions of patterns that we see in the blockworld. So can you provide arguments that looking at "relations" instead of "particles" will make descriptions of patterns better?


It is first time I hear about Regge calculus so it does not work as explanation. I would say that if you want to explain something you have to stick with pretty common things.

RUTA

Here is what I mean by "dynamical laws" as found in the section called "How the universe works" of Sean Carroll's http://blogs.discovermagazine.com/co...-from-nothing/

Let’s talk about the actual way physics works, as we understand it. Ever since Newton, the paradigm for fundamental physics has been the same, and includes three pieces. First, there is the “space of states”: basically, a list of all the possible configurations the universe could conceivably be in. Second, there is some particular state representing the universe at some time, typically taken to be the present. Third, there is some rule for saying how the universe evolves with time. You give me the universe now, the laws of physics say what it will become in the future. This way of thinking is just as true for quantum mechanics or general relativity or quantum field theory as it was for Newtonian mechanics or Maxwell’s electrodynamics.

Depends on what you mean by "better." Of course we think the idea is a "better" interpretation of QM and QFT, but that's subjective. What's not subjective is that it leads to a new approach to unification and quantum gravity (see our CQG paper).

Well, if by "pretty common things" you mean 3D objects evolving in time, I can't help you. That's the whole point -- 4D relations replace 3D objects evolving in time as the fundamental entities and a self-consistency criterion for the 4D relations replaces dynamical laws for the 3D time-evolved objects. Regge calculus is an excellent example, but I can't teach you that here -- you can read about it online, I'm sure. But, briefly, here is how we propose to view Regge calculus per a 4D perspective.

You solve Regge's equations to find the metric g and stress-energy tensor T for each link on the graph. Regge's eqns are obtained from a graphical least action principle, but just like GR, you can't say what you mean by T without knowing g (LHS of Einstein's eqn) and you can't know g without knowing T (RHS of Einstein's eqn). Thus Regge's eqns (counterpart to Einstein's eqn) are a self-consistency criterion, i.e., each solution provides a self-consistent T and g for each link of the graph where "self-consistent" is dictated by Regge's eqns. Now suppose you find a solution and someone asks, "Why is there 5 kg*m/s of momentum on link X?" The answer is, "Because g and T on link X give 5 kg*m/s of momentum and if you changed g and T on X, you'd have to change g and T on Y and Z and ... to solve Regge's equations. That is, you'd have a different self-consistent set of g and T on the graph (a different solution)." Do you see how very different this explanation is than one involving the history of forces acting on some particle? [Sorry for the repeat of this last point on this thread.]

zonde

Then say "dynamics laws" or "laws of dynamics", don't say "dynamical laws".

Of course as a proponent of the idea you should think it's better. But what arguments you can provide for your position? And in whatever way you mean "better".

RBW speaks about two things - blockworld and relations. I am saying that I have no problems with blockworld concept. Worldlines of particles are 4D objects in blockworld.
But please explain how "relations" differ from "worldlines". Both are 4D objects. How can you define (describe) "relations" in RBW (given worldlines)?

RUTA

There are items of personal preference of course, but the most compelling reason we have for believing RBW is "better" than other interpretations of QM is that RBW suggests corrections to GR (as in CQG paper). These changes provide a new path to (indeed, a new understanding of) quantum gravity and unification.


Worldlines in spacetime are constructed from relations graphically -- see figures 1 and 2 of the FoP paper http://arxiv.org/abs/1108.2261. Briefly, Kv = J summarizes the topological situation (e.g., number and "duration" of worldlines involved) and different field configurations on the graph yield different geometries (spacetime configuration of the worldlines). The probability of any particular geometry is given by the transition amplitude computed for the graph, where K is the difference matrix and J is the source vector, evaluated at that geometry.

So, here is how it works conceptually. An experimental process involving objects such as beam splitters, mirrors, sources, detectors, etc. is modeled graphically. Those are the "objects" of Figure 2(a). Now, there is some underlying relational composition of those experimental objects involved in that experimental process as represented by Figure 1(b). In that context, the experimental outcome reflects one of those relations (Figure 2(b)). In this view, there are no other "objects" involved in the experiment, i.e., no "quantum entities" moving as waves or particles among the experimental objects to "cause" the experimental outcome. The "true" quantum/fundamental entities are the relations and they don't "have" worldlines, they "make" the worldlines and spacetime context for the experimental objects. [Note: Space, time and matter are co-constructed from relations, so one doesn't think of "matter in spacetime" or "matter warping spacetime" but rather, one thinks of an inseparable "spacetimematter." This is one way we differ from GR, i.e., one can have vacuum solutions in GR.]

The reason quantum outcomes are statistical is because many different relational configurations can give rise to a particular experimental process. As an analogy, there are many different distributions of molecular velocities that can give rise to a particular temperature for some gas. Thus, one can only ask questions such as, "What is the probability of finding relation X in experimental procedure Y?"

Hope this helps.

zonde

What is represented by boxes in these 1(b) and 2(b) figures? Are they different relational configurations or something else?


There are some quite interesting things in that (http://arxiv.org/abs/1108.2261) paper. But there are things that are rather unacceptable to me. For example this:
"Thus, RBW provides a wave-function-epistemic account of quantum me-
chanics with a time-symmetric explanation of interference via acausal global
constraints[17]. Quantum physics is simply providing a distribution func-
tion for graphical relations responsible for the experimental equipment and
process from initiation to termination. So, while according to some such
as Bohmian mechanics, EPR-correlations and the like evidence superlumi-
nal information exchange (quantum non-locality), and according to others
such correlations represent non-separable quantum states (quantum non-
separability), per RBW these phenomena are actually evidence of the deeper
graphical unity of spacetimematter responsible for the experimental set up
and process, to include outcomes[16][17]. RBW is therefore integral calculus
thinking writ large[16][19]."
I do not see that blockworld means acausality. It just transforms causality into types of patterns that we do observe in blockworld (vs patterns that we do not observe).
So this explanation seems to suggest conspiracy type explanation under cover of blockworld.

Another is confrontation between algebra and geometry. Well I suppose that geometric approach is more appealing for me but just the same I do not like the idea that two approaches would give different results.

RUTA

The boxes are just graphical nodes. We made them boxes so they were clearly visible along parallel links.

The blockworld *contains* causality, but the construct of the blockworld is not *based* on causality, it's based on a self-consistency criterion. Thus, the ultimate (most fundamental) answer to "Why ... ?" is not a causal story. Again, an analogy is Einstein's eqns of GR. If you get caught up in a dynamical/causal (3+1)D story for GR cosmology, you're stuck at the Big Bang with an unexplainable event. But, if you view EEs as a self-consistency criterion, the Big Bang is no more mysterious than any other event on the spacetime manifold.

I'm not sure I understand your comment. Would you please elaborate?

zonde

So are vertical lines like worldlines of equipment?

As I see this self-consistency criterion is the same thing as global conspiracy that experiments show results consistent with entanglement. So it is useless as an explanation.

For example this:
"There has been a very long standing debate in Western philosophy and
physics regarding the following three pairs of choices about how best to model
the universe: 1) the fundamentality of being versus becoming, 2) monism
versus atomism and 3) algebra versus geometry broadly construed; more
generally, which of the myriad formalisms will be most unifying."

RUTA

Yes.


So, you think Einstein's equations are useless as an explanation? It's a matter of personal preference, of course, but certainly there are people who demand explanation be in the form of interacting, time-evolved "things." For them, the reason I gave for why there is 5 kg*m/s of momentum on link X per Regge calculus does not constitute an "explanation." I imagine there were Aristotelians who did not consider reasons per Newtonian mechanics "explanatory" either. Since we are proposing a very different ontology, we are de facto proposing a different understanding of what it means to "explain." That is, our fundamental ontological entities are not time-evolved "things," so our fundamental explanations are not stories about the interactions of such "things."

You said you don't like the idea that "two approaches would give different results." So, in this context you're saying you don't like the idea that "two approaches" would give "different forms of unification?"

zonde

Hmm, then isn't your idea similar to Heisenberg picture where time evolution is applied to operators (measurement equipment) rather than state?


So are you saying that Einstein's field equations are like your consistency criterion?
Stress-energy tensor determines curvature of spacetime. But can there be stress-energy tensor that does not have valid solution for curvature of spacetime in future direction (even if it has valid solution in past direction) and for that reason we exclude particular configuration as a rule?

Wouldn't then all configurations leading to singularities be excluded as a rule. But it isn't the case.

I am not sure it is matter of personal preference. If such an approach as yours makes the idea not falsifiable in principle then it would be preference of scientific research.

RUTA

Our approach represents every piece of experimental equipment as they relate to each other in the experimental process.

Yes, although our equation gives K and J for the transition amplitude, not a classical outcome like Einstein's equations (EEs).

The problem is that the curvature of spacetime is a function of the metric g and so is the stress-energy tensor T. So, which is specified and which is solved for in EEs? The answer is, you must solve EEs for T and g "simultaneously." That's why we use the phrase "self-consistency criterion" to describe EEs -- they constitute a "self-consistent" relationship between T and g.

Do we have GR solutions with singularities? Well, if by "solution" you mean a finite T and g for all points of the spacetime manifold, then there are no "solutions" with singularities. We do make solutions from "near" solutions by omitting singular points, e.g., by omitting the Big Bang in FRW cosmologies. We then assume that the singular point omitted to make the GR solution is finite in some (yet to be discovered) theory fundamental to GR.

I'm assuming that we are only talking about scientific approaches, i.e., those which are in principle falsifiable. Then one chooses which, if any, he is willing to work on based on personal preference.

Ken G

In my view, the RBW approach sounds essentially like being very carefully true to what the scientific process actually is and actually can support, rather than entering into more pretentious modes of thought about what we'd like science to be or what we imagine it should be, but never demonstrably was. So I appreciate your careful description of it. Some of it echoes Bohr's brilliant "there is no quantum world," so perhaps it is an epistemological cousin to the Copenhagen interpretation, though I'm sure you can be quick to point out more essential differences and the potential for predictive character.

Ultimately, I do suspect that to make further progress, physics itself will need to recast its fundamental mission, in language that escapes the naive "God's eye" framing of past physics models, and embraces, perhaps, more internally consistent language like what you are striving for so meticulously. I realize that some still hold that a "God's eye" view continues to be the primary goal of physics ("God is a mathematician" and so forth), so to them, adopting your kind of language about reality would be the death of the mission of physics, rather than further progress in its birthing process. But I don't agree with them.

zonde

RUTA, I have question how relations should look like in spacetime picture of interference. Say how are these two pictures represented using relations:


Basically the question is how do you handle situation where two different paths start and end at the same worldline.

zonde

I do not understand how we can set up experiment that could test retrocausal prediction. And I am not even sure I want to discuss that, sorry. And if you say that GR is making retrocausal predictions then I consider this to be serious argument against GR.

Well I have to admit that to me it seems like process of evolution can produce effects that could look very much like retrocausality while being perfectly causal.