I A new realistic stochastic interpretation of Quantum Mechanics

[Fra]

I mean the interaction and altering the system part, including but not limited to the preparation of some system. In QM one sometimes talks about preparing some system in its thermal state by waiting long enough, but other than that, the active part of macroscopic agents is rarely ever discussed.

This is not easy to even talk about. This gets deep into the actual problems, that IMO requires a new improved "measurement theory". And this doesn't exists yet, but often the first step is to adopt an "interpretation" which changes the perspective so that progress may or may not be easier.

I don't see Barandes so far said anything about this explicitly.

Avoiding actual theory speculation, just making some suggestions from the interpretational stance of "information processin agents", that I think can be used as a platform, for thinking about an improved theory: (By improved theory i do not mean a alternative math that makes the same predictions, I mean a theory that adds substantial new understanding on unification of forces, solves measurement problems, avoids ad hoc finetuning at ever effective level. etc)

• Every perspective, information or expectation is depending on a context/background. This context limits the memory and information processing capacity, of possible statespaces, constructable measurements(interactions). This context is the "agent" or "observer".
  (This would then REPLACE the macroscopic environment, where the hilbert space is encoded)
• The agent/observer is an active parcitipant in a black box. Everything the agent is inferred and stored in its own memory. (The fact that this is limited - unlike the contnext of a hilbert space; has severe implications, when the scale of the agent, becomes similar to the scale of the quantum part)
• Agent - Material system equivalence, suggests that any real agent is of course simply a physical system, so ther must be a dual descrption: One from the inside (ie observations, actions) and one from the outside. But the two descriptions are not equivalent, and I think just like like C.Rovell (in this relational QM) that there is no "external view"; the only physically possible view, is that from another "fellow agent"! Again agent here does not mean physicists. Protons, atoms, electrons, quarks or whatever are "agents". But not macroscopic one

To dress this in an actual model is where the speculation, and it's an open problem.

But roughly imagine the way one agent influence it's environment; where other agents (=matter) exists, is via some stochastic actions(which is stochastic relative to the agent; not relative to other agents!) and here the agents own expectation of the future, is obviously not genereally divisible, it would be a contradicition.

So to the point where I associate to barandes transition probability; one agent at any time, has a "visible" horizon of distinguishable states, and between these there is a transitiion probabilites. This is the context of the "stochastic actions" of the agent. It is how I interpret this. I have now how idea what Baranders thinks of this. Beeing stochastic means there exists no further explanation. What requires an explanation however, is how this state and transition probabilities came into existende. Here I think one needs to complement with an evolutionary picture of evolving agent populations. And that agent population would at some equilibrium then need to be isomorphic to the standard models particle zoo, and phenomenology. The evoluitionary ide supposedly solves the fine tuining.

To try to "play with this", one needs to start with "toy models", of the agents, and consider what happens when a system of such make inferences on each other ~ which of course is just a difference perspective of systems inteacting. Ie we have learning systems, instead of hamilotonian flows. Emergence instead of finetuned infinite spaces. This is actually going to be closely related to interacting ai agents, which uses both reinforced and evolutionary learning. So ultimately I think the future of the qbist interpreation, mates very well with some ai research. That is also the connection to "optimal inference", that QM says what we "infer" about nature, and that is all there is. And if you take this very seriously, and consider that all matter is like this, then physical forces could be like a litteral game of expectations. The question of what is the "true" ontology is not possible to distinguish from the normal infereence and learning process.

This is my view in brief of this, not sure if it make anything clerer and hope it's not considered specualtions, because they are not IMO. Speculations needss to be much more explicit, this is why this is fuzzy and interpretational only. It otherwise gets impossible to discuss our views open problems or interpretations of current research such as barandes.

It is just my personal views withing the context of the wider family of qbist or interacting agent interpretations, and it's from this stance i see Barandes works as nice, but alot is missing. But as noone has the full answers, not need to pick on incompletness, he is at least providing parts of a new perspective.

/Fredrik

 

[physika]

the question is why should there be observer-dependence?

Right, Why ?

and the process of "individuation" of "observers", shady, ontologically; arbitrary or unfounded.

......

 

[Fra]

Sure, but the question is why should there be observer-dependence?

Right, Why ?

and the process of "individuation" of "observers", shady, ontologically; arbitrary or unfounded.......

I see it as an unavoidable connectivity between ontology and epistemology. They are in my view, not opposites, they are complementary. You can't have one without the other.

Everything needs a context/foundation/premise, to build onto.

For example, mathematics and needs a context, which is a bunch of axioms; they can also be accused for beeing shady, ontologically; arbitrary or unfounded?

Also to be able to hold/encode information (of anything) you need a context, which is some memory structure. One may say this memory microstructure is shady, ontologically; arbitrary or unfounded? For example the microstructure of a string in an embeddd space. This is the CONTEXT of string theory; and to say that it is shady is probably and understatement.

To be able to formulate a question; or construct a measurement; you need a language, or context for the preparatory processes. This is not something that happens in vaccuum.

So scientific knowledge needs to be stored somewhere, and the process of inquiry needs a context. At human science level this is of course physisicsts, advancing human technology, that is rooted in solid macroscopic realm which is effectively classical.

So ther has to be a starting point; a context, for holding/encoding an expecatation, and to structure and manipulate input, to produce output. There is an unavoidable need for this as I see.

In physics this has always been the case; SR and GR the "observer" is simplified to an "observational coordinate frame"; the "observer" is not thought of as having a microstructure etc". In normal QM, we still ahve the spacetime background, but also we need the "context" to accumulate and hold statistics somehow, to be able to verify this in real experiments, preparattions needs to be controlled to the point that they can be repeated, and we collect the dat. This requires a huge non-trivial context. All this is the agent/observer.

But this revision of the contex is incomplete, the divergenses and renormalisation that keep popping up in physics, is I think beceuase we "force" too much information into the theory context; this is pathological and I think it's related to exactly this; our understnading of the "context" of the theory, that this is dynamical and should be thought of as an "agent" that is interacting, not passive.

This is what this is about for me. And the puzzle is still there.

Why do interference patterns occur due to adding slits?

For me the alternative explanation alterntaive to the reglar "complex wave interference" stuff, is that the whole system can be tought of as interacting agents/(subcontext,subsystems

The source, slit and detector.

The interaction between these parts (in the interpretation I subscribe to) can be DESCRIBED by an external observer, but then the evolution has to be inferred with some tomographic process first. The better expolanatory view is from the perspecitve of the parts themselves, and here the source, the slit and the detectors have initially information and expectations of each other. All of them are complete and biased, but that is how it is. And the interaction between these is best understood not in terms of hidden reality, but in terms of how theire expectations influence their actions to the other parts, and this will then give the interference effects. And parts of this involves, that the expected evolution relative to each part, are never divisible, the "divisions" are only where the parts update its expectation via input/output operatins.

Attempting to go into more detail would take us into speculations, as one has to assume "properties".

And finally; the "solution" to the "you can't have one without the other" and the lack of objectivity is supposed to be; emergence of objectivity via evolutionary process. And the insight is that there is not unitary description of evolutionary processes; it's the wrong approach. This is where agent based models provide better perspective than system dynamics.

/Fredrik

 

[gentzen]

One unintuitive feature of QM is that you have to interact with a system to observe it.

How can you possibly or reasonably observe something without interacting with it? For me this is as intuitive as it gets, the opposite is rather unintutive for me.

Are you really sure that it is intuitive? Let's say "we" (i.e. our observatories and telescopes) look at Proxima Centauri, resolve the dark and bright lines in its spectrum, study spectral doppler shifts and brightness variations, and use this data to make deductions/inferences about its chemical composition and its planets. It is more than 4 light years away, so in which sense is it intuitive to you that we interacted with this system, including

And this interaction alters the system.

In fact, thinking about it now, my guess is that our observations of this system didn't actually alter it. But not because it is macroscopic or far away, but because we didn't prepare it (not even the tiniest part of it). And I guess the same is true for observing a decaying radioactive nucleus. But the difference here is that we could have prepared it (even so we rarely do it, if ever).

Classically, I can also alter a system without learning anything about its state prior to the interaction. How does QM change this part? Why can‘t I just forget what I learned during the interaction, if QM should force me to always learn something? Perhaps because my own state was altered nevertheless?

As I see QM, it is not about random (or specifically suboptimal) inference, as there is no lower bound on that. It is about optimal inference, it what is the maximal amount of information we can have about a another system; given some contraints.

Thanks, this is a surprisingly fitting answer to my question. Except that for me, the question already starts earlier, namely what exactly is the analogon of the quantum "observation" situation for the quantum "alterning" situation.

But when you consider a more realistic observer, ie agents with finite mass, then information capacity and backreaction can no longer be ignored. And this is when it becomes interesting, but this part is also which is not included in current theory and is an open problem. Taking this seriously in a future model, must associate with each "observer" a natural regulator, which implies lossy retention, and the "backreaction" is simply the update of what is normally considered the "background".

I guess you are proposing "natural regulator" as a nicer name for the quantum "alterning" situation. You are right, I am still looking for a good name, which better conveys this concept. Maybe I should have used "feedback-free control" or "blind control". But I also don't like those. I just want to have a focus on "doing" and "action" without any special attention to observation, not necessarily complete absence of observation.

 

[gentzen]

But this revision of the contex is incomplete, the divergenses and renormalisation that keep popping up in physics, is I think beceuase we "force" too much information into the theory context; this is pathological and I think it's related to exactly this; our understnading of the "context" of the theory, that this is dynamical and should be thought of as an "agent" that is interacting, not passive.

You hope that a change in "interpretation" will fix mathematical issues? Issues whose root cause is no longer a complete mystery, but can today be seen for example in the context of the "Wilsonian view" (ultraviolet divergences), in the context of "boundary condititions"/"topological perspective" (infrared divergences), or ... (point particles vs 1D string) ... (add your own favorite perspective here)?
Why does every solution for a specific problem always has to also cure cancer and solve world hunger?

One thing that Barandes does better than you is that he actually publishes his ideas, even if they are still unfinished and slightly flawed. My impression is that you will never start to publish your thoughts, because they will never be as polished and finished as you hope for, and won't solve all the problems they could possibly solve.

 

[Fra]

Are you really sure that it is intuitive? Let's say "we" (i.e. our observatories and telescopes) look at Proxima Centauri, resolve the dark and bright lines in its spectrum, study spectral doppler shifts and brightness variations, and use this data to make deductions/inferences about its chemical composition and its planets. It is more than 4 light years away, so in which sense is it intuitive to you that we interacted with this system

By registering/consuming the radiation, and instead emitting something else (noise/heat), we modify the environment of the star, which has consqeuences in principle for the stability of the star. Obviously the effect is minimal in your example, but the principle is clear to me.

I guess you are proposing "natural regulator"

Yes one that has a physical basis, unlike "fictional" regulators used in renormalisation. With the natural regulators built-in, the divergence should not appear in the first place. Without speculating about the explicit relation and relation to entropy etc, intutively, the mass of an agent, is a highly probable natural regulator. In inference this would then also likely relate to confidence or "inertia" of statespaces. This is a mathematical problem, but it is alot easier to think about if you can find an intutitive handle

/Fredrik

 

[Fra]

You hope that a change in "interpretation" will fix mathematical issues?

Of course not, we will not solve anything by "pure interpretations". For the me change of interpretation is a way to align and focus the research in a specific direction. The fix is a new theory. But how do we find a new theory without intutive guidance?

One thing that Barandes does better than you is that he actually publishes his ideas, even if they are still unfinished and slightly flawed. My impression is that you will never start to publish your thoughts, because they will never be as polished and finished as you hope for, and won't solve all the problems they could possibly solve.

That's a good point. But my ideas grind slowly, as i have a normal job. I like to get things right, rather than be fast. I have no pressure to publish anything. When I feel it's worth publishing it will come, but there is enough mumbo jumbo already that I don't need to add more.

/Fredrik

 

[nPoE]

Seems the obvious implication of this thread is that many in the field disguise their bitterness and ego in the guise of rigor while it not being entirely clear they are rigorous. I am very unsure that education makes us better in the human sense. Its a pity, so many Elons.

 

[gentzen]

Seems the obvious implication of this thread is that many in the field disguise their bitterness and ego in the guise of rigor while it not being entirely clear they are rigorous. I am very unsure that education makes us better in the human sense. Its a pity, so many Elons.

Don't missinterpret my exchange with Fra/Fredrik as bitterness. I am having this exchange with him, because I know that he can understand the direction into which I am thinking, and is willing to answer and discuss this stuff.

As for Barandes, I guess you mean that me and the others who are skeptical about his latest paper ask for more rigor than we ourselves would be able to provide. Yes, I also would like more rigor. But more than that, I wish Barandes would correctly put his work into the context of existing investigations into the foundations of QM. Comparing his work to the Feyman path integral formulation is not helpful here.

 

[Fra]

I think there is two kinds of "rigor" here, that needs to be in balance.

Mathematical rigor and what one might call perhaps "conceptual rigor/clarity" or maybe there is a better term?

Axiomatic constructions of physical theories can be as rigorous as mathematics. But if the mapping of this axiomatic structure to our conceptual understanding of physical reality is too ambigous, then we lack conceptual rigor.

But it seems this conceptual rigor is related to the choice of interpretation, and choice of primitive ontologies, almost like an axiom system for conceptual understanding; so for any given mathematical theory there is perhaps an interpretation where the conceptual clarify is highest.

In this case, it's the mathematical description of "observation" "observable" and "observer" that lacks a matching coherent conceptual clarity; and intutitively there is also some mismatch here as the mathematical versions here more corresponds to some asymptotic scenarios. That's generates the obvious question; what are the generalisations of the "observables" and "obserevers" to the actual non-asymptotic cases? These cases are what I have labeled "inside observers". Ie. more realistic observers, in constrast to the asymptotical limiting cases that I think QM and QFT corresponds to.

But the insight is also that this is fine for small subsystems like atomic systems! Because we meet the asypmtotic approximates well enough in finite times in our experiments! But what when we dont get away with this? Then we can not hide at the horizon anymore.

If we don't grasp these very basic things, playing around with mathematical models in isolation will not increase any understanding, at least it's how i feel about this.

/Fredrik

 

[iste]

It will release in a couple of days, and then we have to watch about 1-2 hours of it, it can wait.

Do you happen to know when it is coming out?

 

[pines-demon]

Do you happen to know when it is coming out?

2h ago.

Here it is:


I will update later this week, whenever I get time to listen to it.

 

[iste]

2h ago.

Here it is:


I will update later this week, whenever I get time to listen to it.

Ah, thanks. Good timing.

 

[pines-demon]

Ah, thanks. Good timing.

Ok here is my review of this second part of the podcast. The podcast is long but very interesting from a history of physics perspective. I think Barandes clarifies some misconceptions that some physicists have about Bell and other interpretational issues in quantum mechanics. He also proposes some interesting ideas like that someone should work on a classical probabilistic theory for general relativity (inexistent as far as he knows).

However the podcast is too long compared to what he actually get. Concerning NMIS processes he has some favorable things to clarify:

• Barandes dropped describing his reformulation as a memory effect
• He does see his reformulation as an interpretation and argues that it is a better alternative than Bohmian mechanics
• His reformulation does not indicate what is the true nature of physics (it could be particles, waves, fields, qubits or whatever, the reformulation is very flexible)
• He addresses my criticism of the misuse of Reichenbach principle, he agrees that is not exactly what Bell meant (he says that somebody pointed that to him)

These are the things that I do not get

• He says that his reformulation bypasses Bell factorization (or Reichenbach principle) by redefining the "microscopic theory of causation". The details are apparently in this paper https://arxiv.org/abs/2402.16935 and in his talks. However as I have said before his Bell talk does not discuss his redefinition. I will try to read the paper.
• He says that his approach bypasses all the need of interference and complex phases in the presence of a measurement device. How? It is unclear.
• [From podcast part 1] He still did not provide a simple example of indivisibility. We still have to wait for his double slit interference paper.

So again he is claiming a new interpretation that erases the need of quantumness (interference and entanglement). I still worry that his picture is not that simple and that he has just found some mathematical duality, but I might be wrong. Hope this helps.

 

[Fra]

https://arxiv.org/abs/2402.16935

Thanks for the link, the talks and paper deserves proper reading. I will get back as well when i had time to read/listen.

I quickly skimmed a bit of it + the talk and I again tend to get along well with his reasoning, and he acknowledge serious deep issues where he has no answer which are keys. The fact that he mentions qm + gr issues and howto view spacetime indicates to me that he at least does not hold a naive view on this.

If i remeber correctly from an incomplete listening in the car yesterday he pondered about that a stochastic formulation of gr may automatically gi e qm? I like it. The hunch is also the the quest for local beables that respects some causal locality and ia stochastic is if not the same closely relates to the "intrisic" or "inside observer" views that current theory explicitly lacks. He argues it seems that bell inequality does not forbid this, and i agree. He seems to highlight the "right problems" and this encourages me to read more carefully to see if i can find the deeper connection

/Fredrik

 

[JC_Silver]

• He says that his approach bypasses all the need of interference and complex phases in the presence of a measurement device. How? It is unclear.

To me it seems that he is arguing that indivisibility would be akin to superposition, however instead of the particle "becoming" a wavefunction and interfering with itself, the particle (or small system) is in a state where its behaviour is unknown, it could be anything (eg. particles aren't real, many worlds are happening at the same time, spacetime is superweird, strings are stringing, whatever) that is non-Markovian and indivisible (t' is not independent of t and the system's evolution cannot be divided such as t->t'=t->t¹+t¹->t'). It's not that the particle itself became a wavefunction, but that the particle is following some physics between point t and t' and if you want to know the probability between t and t' you can use a wavefunction, but that doesn't tell you what actually happened between t and t', because in an indivisible processes there is no t->t¹+t¹->t' that gives a correct prediction of t->t'.

The wavefunction (and with it interference and complex phases) describes how our expectation of the probability should evolve, but doesn't really describe the reality between t and t', because for us to be able to actually tell what is happening between t and t' we'd break indivisibility.

(Honestly, I wrote several paragraphs here but everytime I finish and read it, it turns out I have just described regular old QM using 'indivisibility' and 'division event' in place of 'superposition' and 'collapse')

 

[Fra]

I looked at https://arxiv.org/abs/2402.16935 and I think the interesting

These are the things that I do not get

• He says that his reformulation bypasses Bell factorization (or Reichenbach principle) by redefining the "microscopic theory of causation". The details are apparently in this paper https://arxiv.org/abs/2402.16935 and in his talks. However as I have said before his Bell talk does not discuss his redefinition. I will try to read the paper.

The mere reformulation from indivisible stochastics to hilbert formalism is not the most interesting part, it is in a way some equivalent formulation as others suggested, but the important part (for me at least) is the understanding of causation, but now as i read what he suggests, it does looke like ideas diverge from what I hope for.

That parts that is conceptually unclear to me is this when he tries to define the new improved principle of causal locality, he starts by considering a decomposition one unistochastic system into two parts, that are furthermore spacelike separated on page 11... and then he goes on from there.

This seems very nontrivial to me, when trying to squeeze this through the "agent perspective", and has two suspicious parts.

The first issue is that the decomposition of one system into independent parts us problematic from how I want to see it, as the "view of one agent" is always holistic; as I think in a way there is only one "system" from the perspective of an agent; and it is the whole environment. If you decompose it into parts, there is bound to be some relation - at least via some memory capacity constraints, that leaves at least a subtle dependence between the two, in some holographic sense that an image of everything is always encoded in every part, suggesting that a complete independence in principle of even seem counterintutitive to me.

The other issue is that he introduces space (which I expect eventually to be emergent in some way; after all in his early discussions the index of states in the configuration space is abstract! It is an abstract space of distinguishable states, there is at that pooint now reference to 3D or 4D metrics; but now from nowhere spacelike notion enters. this is too fast for me for a conceptual reconstruction; but fine for a reformulation).

I'll ponder about this a bit more, but this is my current state of confusion on the matter. I think the emergence and origin of the transition matrixes; and in particular how it works when you consider a union of two such systems, is wherin the possible clarification to this may be found?? And this unavoidably brings us to the topic of ununification of both all forces and the metric distanaces between parts (space).

But again Baranders mentions in the youtube talk that he thinkg there is alot of research to be done, that can explore many things, including seeking a stochastic interpretation of GR; and perhaps that can yield surprises... I think so to.

So I think the difficulty to understand this, or Barandes ideas is that many problems are interconnected. So it's a mess, but a very interesting mess.

/Fredrik

 

[Fra]

(Honestly, I wrote several paragraphs here but everytime I finish and read it, it turns out I have just described regular old QM using 'indivisibility' and 'division event' in place of 'superposition' and 'collapse')

I think you have a point here, and it's why I think a better understanding of nature of causation, rather than a new mathematical formulation, is the main take away I was hoping for here.

If we are just as confused by indivisibility or non-markovianity as we we with the hilbert features, what have we gained. And to understand these things, I think they causation or even what causation means in a "newtonian paradigm/schema", is the heart of the matter. Baranders stress this as well in his youtoube clip, and I enjoyed to hear it.

/Fredrik

 

[pines-demon]

Hello, excuse me for bothering you. I am a beginner, and I would like to understand what the potential issues are in Barrande's approach.

Most common potential issues pointed out are that it does not provide an interpretation (or at least not an easily dissectable one). Also it claims to deflate any issues of quantumness (entanglement might be local, interference is an illusion and more).

Some of us just think that he found a nice mathematical relation between quantum systems and a particular kind of stochastic processes. The interpretational power of that analogy is still under discussion.

 

[physika]

stochastic GR

......

 

[gentzen]

I have another question: would it be possible to test Barrande's approach to confirm that it reproduces the experimental results of quantum mechanics (such as the violation of Bell's inequalities or the GHZ state), which would be an indication of its viability?

I don't think so, because

It is not a new formulation, because it is not comparable to Feynman's path integrals, to Schrödinger's wave mechanics, to the matrix mechanics of Born and Heisenberg, or to Dirac's transformation theory. And it is simply missing the resources to go from physical situation to mathematical description.

It doesn't make predictions. So it is not in the business to reproduce experimental results or not.

And it should be the task of Barandes to clarify how his approach fits into existing categories. I personally would put into the "quantum reconstruction" category. But if Barandes would propose another fitting category, that would be fine for me too.

Finally, Barrande with curt jaimungal has published a new video on his approach if that might interest you.

You mean the one mentioned in this post? Or the recent ToE video with Jacob Barandes and Manolis Kellis mentioned in this post? Or is there yet another new one?

 

[gentzen]

But again Baranders mentions in the youtube talk that he thinkg there is alot of research to be done, that can explore many things, including seeking a stochastic interpretation of GR; and perhaps that can yield surprises... I think so to.

stochastic GR;

Not sure what you mean by "". Barandes really mentioned it in the video, just like Fra reports. You want us to give a specific timestamp where he does? Or you mean that Barandes' idea is not so great after all?

 

[physika]

Not sure what you mean by "". Barandes really mentioned it in the video, just like Fra reports. You want us to give a specific timestamp where he does? Or you mean that Barandes' idea is not so great after all?

Sounds Interesting, but...
let me digest first.

 

[iste]

He says that his reformulation bypasses Bell factorization (or Reichenbach principle) by redefining the "microscopic theory of causation". The details are apparently in this paper https://arxiv.org/abs/2402.16935 and in his talks. However as I have said before his Bell talk does not discuss his redefinition. I will try to read the paper.

My issue is that what he shows doesn't seem to be that novel, but just seems to reiterate something like the kind of no-signaling property that is already well-known, as someone else in the thread pointed out. Its then unlikely to convince anyone into thinking that quantum mechanics is local - i.e. "if I already knew about this property when I thought quantum theory was non-local, how is reiterating it going to change my mind?". I guess though that with no collapse, a significant purported source of non-locality is gone from Barandes' theory.

Funnily enough, there is non-local causation in the system before measurement, under his definitions; but he appeals to the fact that this is directly because the indivisible stochastic matrices encode the local interaction at t0, and so this non-local causation is due to the local interaction in the past light cone. I think its fair to criticize the Bell inequalities in the sense that the common cause assumption Barandes talks about isn't applicable to the initial local interaction, but neither does his alternative view of causation seem applicable either. I think appealing to the properties of the indivisible transition matrix may still actually be fair to justify locality here, and maybe more interesting than the no-signalling result. But, because there is no transparency about why and how exactly indivisibility occurs (but I think what indivisibility means is relatively straightforward) this doesn't seem so satisfying.

I think another fair criticism of Bell inequality is the observation that while factorizability corresponds to Bell locality, there is also a strict equivalence between factorizability and the existence of global sections (e.g. joint probability distributions): e.g.

https://iopscience.iop.org/article/10.1088/1367-2630/13/11/113036/meta
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.48.291
https://pubs.aip.org/aip/jmp/articl.../Joint-distributions-quantum-correlations-and
https://link.springer.com/chapter/10.1007/978-94-017-0849-4_6

This seems like a major conflation since it implies locality must be characterized by a global joint probability distribution despite the fact that this same property systematically breaks down regardless in quantum theory due to non-commuting observables. The question is then:

Why does locality / local causality require the presence of joint probability distributions especially when we are talking about the kinds of things that cannot be straightforwardly plugged into the common cause criteria Barandes mentions?

This doesn't seem reasonable me (but I very well could be missing something here!).

Albeit, I don't think someone like Barandes can truly succeed in convincing that the conception of local causation he favors is truly valid here until he can give an intuitive explanation of how the measurement results seem to depend on both spatially separated measurement settings in a Bell scenario.

He says that his approach bypasses all the need of interference and complex phases in the presence of a measurement device. How? It is unclear.

He is just saying that if you were to translate from the Hilbert space representation to the indivisible stochastic one, you cannot reproduce the quantum predictions without explicitly including measurement devices as components of the indivisible stochastic system. When you translate back into the Hilbert space representation, the measurement device's role in disturbing the stochastic dynamics is incorporated into the phase so that the measurement device no longer is required to be explicitly represented in the measurement process. The need to explicitly incorporate the measurement device is also shared in Bohmian mechanics: (section vii, from page 49)

https://arxiv.org/abs/1206.1084

It also seems to be the case in Nelsonian stochastic mechanics and I think there is some reason to believe that it also corroborates what he says about the phase.

 

[Fra]

Funnily enough, there is non-local causation in the system before measurement, under his definitions; but he appeals to the fact that this is directly because the indivisible stochastic matrices encode the local interaction at t0, and so this non-local causation is due to the local interaction in the past light cone

I think your issues are related to those I have. The problem I have is explicitly that if we have a new understanding of causal influence, then this likely must come with implications or constraints on the possible transition matrixes (or equivalently the possible hamiltonians). And trying to understand the construction and structure of the transition matrix or hamiltionians in fundamental ways, is precisely one of the things the quest for unification of forces is about. And if one starts to talke about "spacelike" distances between PARTS of this transition matrix, that really needs qualifications I think.
If we just "assume there is an transition matrix" in this configuration space and we understand that no better than the "assume there is this hamiltonian" in this hilbert space, then IMO we have not gained much conceptually.

But I do see a way to make something out of this, but Barandes reasoning in https://arxiv.org/abs/2402.16935 takes a different path from what I would prefer.

OTOH, if you really want to question the makeup, structure and phenomenolgoy of the space of all transition matrices from first principle abstract configuration spaces, then you obviously immediately dissolve spacetime as we know it to (this is also the connection to reconstructing GR). And things really get complicated. Much more complicated. In particular it gets circular, so an evolutionary approach seems unavoidable; to avoid finetuning situations. Does Barandes want to avoid going there?

The real question, is where the "observer/agent" is in Baranders view? Specifically the subsystem Q and R he talks about on page 11; do we associate them to TWO different observers, or a decomposition of the whole system from the perspective of one observer? For me, this makes a big difference.

For me personally, what is clear is that the causal influence on the intrinsic actions of two observers are limited to their intercommunication. In the two abstractions here; agent-agent interactions, vs part-part interactions from the perspective of the "newtonian schema/paradigm", there is as Baranders also hints a in his video, not even clear what "causal influence" MEANS in the newtonian paradigm? All we can infer is a correlation, the "causal notion" is a fiction - UNLESS we switch to the agent perspective, then it IMO becomes clear. The causal influence is simply that the agents reactions to the extent that its not just stochastic, is only modulated by it's inputs (as received from the environmnet). So no physical communication - no influence; is built in.

If we associate internal observer to Q and R, what Baranders says makes a little more sense, but brining in spacemeasures this fast, without explaining how the relation between the agents, define this metric withou referring to external spacetime.

My given all the research questions Baranders mentions in the youtube video, I it seems thta this stochastic quantum correspondence is by no means meant to be "complete". So it is probably unfair to expect all solutions at once. But at the same time, it is at least the promise of solutions, that motivates most of us I think for seeking new perspectives, from where solutions problems become more feasible.

And I think gentzen has a good point, that having the ambition to solve at once becomes unsurmountable; yet when you are convinced that things are deeply interconnected, progress becomes difficult and every step forward is unavoidably going to have some deep flaws. So I think we might need to view the new correspondence with an open mind.

/Fredrik

 

[iste]

The real question, is where the "observer/agent" is in Baranders view? Specifically the subsystem Q and R he talks about on page 11; do we associate them to TWO different observers, or a decomposition of the whole system from the perspective of one observer? For me, this makes a big difference.

Q, R, A and B in that paper are all just physical systems as they would exist objectively and independent of any kind of observer. A and B are physical systems that take the role of measurement devices; A and B are therefore observers but in the deflationary sense that an observer is just any kind of physical system whose states have some specific relationship to the states of other systems that they are measuring. Nothing special. The whole system including A, B, Q, R is a physical system as would objectively exist independently of some other observers. In fact, you see in same parts of that paper that Barandes explicitly wants to do away with the notion of agents in his description. It is agent-less causality.

Causality may seem easier from an agent perspective; but then, I don't think we need agents. Furthermore, I think the idea of an agent is a construct that can always be deflated - like how a human's agency is nothing above what a brain can do, which in itself is just a physical system. Agentive causation is then in some sense completely illusory. It may be a useful, even "real", construct in some scientific and other intellectual fields; but from the perspective of physics or neurobiology, it is like a convenient fiction (perhaps idealization or stop-gap is better). Agentive causality then reduces to the kind of causality that Barandes is talking about in the paper - about atoms influencing each other in a directed ways, at least trying to construct a notion of that which makes sense.

 

[Fra]

Q, R, A and B in that paper are all just physical systems as they would exist objectively and independent of any kind of observer. A and B are physical systems that take the role of measurement devices; A and B are therefore observers but in the deflationary sense that an observer is just any kind of physical system whose states have some specific relationship to the states of other systems that they are measuring. Nothing special. The whole system including A, B, Q, R is a physical system as would objectively exist independently of some other observers. In fact, you see in same parts of that paper that Barandes explicitly wants to do away with the notion of agents in his description. It is agent-less causality.

Causality may seem easier from an agent perspective; but then, I don't think we need agents. Furthermore, I think the idea of an agent is a construct that can always be deflated - like how a human's agency is nothing above what a brain can do, which in itself is just a physical system. Agentive causation is then in some sense completely illusory. It may be a useful, even "real", construct in some scientific and other intellectual fields; but from the perspective of physics or neurobiology, it is like a convenient fiction (perhaps idealization or stop-gap is better). Agentive causality then reduces to the kind of causality that Barandes is talking about in the paper - about atoms influencing each other in a directed ways, at least trying to construct a notion of that which makes sense.

I see what you are saying, but my own biggest reason for thinking this way is not something that is evident in Baranders paper. My bigger perspecitve is unification, not just "interpretations". There is more to it than the fact that as we know already, there are two ways to model systems of interacting parts;

1) System dynamics (meaning there is differential equations), state spaces and initial or boundary conditions. This is a top down approach. It typically requires finetuning of the system dynamics; in a ways that makes it "effective", it is not always obvious how to parameterise a differnt system.

2) Agent based models, is a bottom up approach where one models the local interaction between the parts, and the big picture is emergent. This often leads to better insight into local mechanism.

The exploit I see is that agent based models, has chance to put strong constraints in theory space - just like string theory; except string theory is a bit weird; the continous string embedded in a higher dimensional background is non-trivial and has it's own finetuing problems. It's background dependence is what prevents it from beeing what it could have been.

So my personal preference for the agent centerted view goes beyond what we discussed so far. But going into that is off topic.

/Fredrik

 

[gentzen]

Causality may seem easier from an agent perspective; but then, I don't think we need agents. Furthermore, I think the idea of an agent is a construct that can always be deflated - like how a human's agency is nothing above what a brain can do, which in itself is just a physical system. Agentive causation is then in some sense completely illusory.

I would not be so quick in dismissing "agents" at our current state of "capabilities". The interpretation of statistical results from randomized controlled trials currently needs the assumption of active interventions. And Judea Pearl's causal inference didn't (yet) manage to get completely rid of this either:

These are causal questions because they require some knowledge of the data-generating process; they cannot be computed from the data alone, nor from the distributions that govern the data.

I rather think, before getting rid of agents, we first have to embrace them more seriously:

Or maybe more aptly, it suggests an old time astronomer like in Newton's times watching the planets, moons, and stars without any possibility to alter their course. It does not suggests a modern NASA scientist designing swing-by (gravity assist) maneuvers to steal a tiny amount of the energy of some planet or moon to let his spacecraft save fuel.

Of course, the course of the planet or moon is not significantly altered, but the course of the spacecraft is. You could model the spacecraft itself as an agent, because it has thrusters which are effectively controlled by intentions (i.e. final causes). It can also make sense to only model the ground station as an agent, because the communication delay to the spacecraft might be important. But beyond that, the usefullness and explanatory value of the model would rather decrease if you try to remove agents even further.

I admit that trying to develop theoretical frameworks which are less dependent on agents for their explanatory power is a worthwhile goal. I am in full support of A. Neumaier's thermal interpretation, which includes a convincing non-subjective interpretation of probabilities. But we should also admit that we are not there yet, and that we currently have no idea how that goal to get rid of agents in our models could ever be reached.

It may be a useful, even "real", construct in some scientific and other intellectual fields; but from the perspective of physics or neurobiology, it is like a convenient fiction (perhaps idealization or stop-gap is better).

Maybe it is a "stop-gap", but "gap" suggests something small. But it is not a "small gap", it is a "huge chasm"!

Agentive causality then reduces to the kind of causality that Barandes is talking about in the paper - about atoms influencing each other in a directed ways, at least trying to construct a notion of that which makes sense.

There is also a question as to how many agents are there. Fra's initial answer to my "in which sense is it intuitive to you" question was a wordy "the principle is clear to me":

Are you really sure that it is intuitive? Let's say "we" (i.e. our observatories and telescopes) look at Proxima Centauri, resolve the dark and bright lines in its spectrum, study spectral doppler shifts and brightness variations, and use this data to make deductions/inferences about its chemical composition and its planets. It is more than 4 light years away, so in which sense is it intuitive to you that we interacted with this system

By registering/consuming the radiation, and instead emitting something else (noise/heat), we modify the environment of the star, which has consqeuences in principle for the stability of the star. Obviously the effect is minimal in your example, but the principle is clear to me.

But in a later seemingly unrelated post, Fra gave a better answer, namely that it isn't a multiagent perspective at all:

The first issue is that the decomposition of one system into independent parts us problematic from how I want to see it, as the "view of one agent" is always holistic; as I think in a way there is only one "system" from the perspective of an agent; and it is the whole environment. If you decompose it into parts, there is bound to be some relation - at least via some memory capacity constraints, that leaves at least a subtle dependence between the two, in some holographic sense that an image of everything is always encoded in every part, suggesting that a complete independence in principle of even seem counterintutitive to me.

The picture is just one agent, one system, one environment. Which is an important point. If you look at the explanatory role of agents in models, one agent always seems to be enough (from the perspective of physics or neurobiology).

So I guess we should at least stay long enough in the picture with "agents", until we have clarified how many agents would actually be helpful for explanatory strenght (and insights), for a specific given scientific problem.

 

[Fra]

I rather think, before getting rid of agents, we first have to embrace them more seriously:

I agree, but "getting rid of" them meaning what? They are after hand the handles into actual observation and interaction. We need to "break" this invariance to touch based with reality.

IMO a conceptually undeniable argument against "agent/observer dependence", is the principle that there is no preferred observer, among the set of possible choices. But this is not the same as saying you do not need an observer! Without the set of actual obserers, the principle is empty!

This is the key constructing principle in both special and general relativity for the "class of observers" that are just generated by moving around in spacetime.

One way to attempt to satisfy this requirement is if you find a transformation that defines the observer equivalence, for example the poincare transformation. If we can do this, great and fine.

But such an equivalence transformation presumes that all observers, can encode the same amount of information and perhaps even unlimited information; otherwise there can't possible be an equivalence. This means, different observers have different amount of information and even different information as all records may be lossy, but it does not necessarily mean one is more right.

If this is not so, the principle of no preferred observer, does not imply observer equivalence, but implies what I think of as "observer democracy" (which indeed gets more complex).

But in neither case do I think it makes sense to think that the observers is not needed as elements in the fundamental theory.

/Fredrik

 

[iste]

I would not be so quick in dismissing "agents" at our current state of "capabilities". The interpretation of statistical results from randomized controlled trials currently needs the assumption of active interventions. And Judea Pearl's causal inference didn't (yet) manage to get completely rid of this either:

Agents don't have some  essential role in Bayesian causal modelling, which is what Barandes is using. As I said in the rest of my post, you can deflate the role of an agent in a way that is like any other event or any other "data generating process".

But we should also admit that we are not there yet, and that we currently have no idea how that goal to get rid of agents in our models could ever be reached.

It genuinely doesn't seem that hard to me. Barandes' approach has no agents or observers and I don't see why it should need them and I don't think anyone here has given any kind of tangible reason that the role of observers or agents should be made more important and special. If Barandes theory were able to recreate all the predictions of quantun theory, why need them? Its just completely unnecessary.