I Is the Hamilton-Jacobi Formalism a Classical Analogue to Quantum Wave Functions?

[fanieh]

Which he did.That's correct.Yes.Exactly.

Demystifier. In Bohmian Mechanics. Do the polarization of photons or electrons have definite values before measurement in the double slit experiment. Any paper how to analyze how these interact with the double slits?

Second. What is the counterpart or analogy of the Hamilton-Jacobi equation in Quantum Field Theory? If trajectories and actual particles are in the beabble in Hamilton Jacobi equation in BM.. what are the beables in HJ version or counterpart of QFT? Quantum Mechanics is just very low energy and doesn't really model the real world as it's in Galilean space.. we need at least special relativity & QM as minimum even as effective field theory.. or even use the full load of general relativity and QFT as this is the world we live in.. Planck scale is part of our world. What's the best implementation of GR and BM right now or out there? Thanks.

 

[vanhees71]

I think, you cannot treat photons in BM, because they are relativistic for sure, and there is no working relativistic version of BM. On the other hand for massive particles non-relativistic QM works perfectly well in its realm of applicability, which is a great deal of atomic, molecular, and condensed-matter physics!

 

[Demystifier]

Demystifier. In Bohmian Mechanics. Do the polarization of photons or electrons have definite values before measurement in the double slit experiment.

No.

Any paper how to analyze how these interact with the double slits?

See e.g. https://arxiv.org/abs/1305.1280

Second. What is the counterpart or analogy of the Hamilton-Jacobi equation in Quantum Field Theory? If trajectories and actual particles are in the beabble in Hamilton Jacobi equation in BM.. what are the beables in HJ version or counterpart of QFT? Quantum Mechanics is just very low energy and doesn't really model the real world as it's in Galilean space.. we need at least special relativity & QM as minimum even as effective field theory.. or even use the full load of general relativity and QFT as this is the world we live in.. Planck scale is part of our world. What's the best implementation of GR and BM right now or out there? Thanks.

There are no unique answers to those questions, various different proposals exist.

 

[fanieh]

No.See e.g. https://arxiv.org/abs/1305.1280There are no unique answers to those questions, various different proposals exist.

Ok. Btw.. is there a QFT version of MWI?
BM is just a MWI with position preferred basis chosen.. if we remove the position preferred basis.. it's back MWI in essence.
In the pure unitary universe without preferred basis. Have you written a paper or are you sure 100% that the interaction Hamiltonian can't select the position preferred basis? And it needs additional assumption in the universal wave function?

 

[Demystifier]

Ok. Btw.. is there a QFT version of MWI?

Yes.

Have you written a paper or are you sure 100% that the interaction Hamiltonian can't select the position preferred basis?

To a certain extent it can, but not in the ontological sense.

And it needs additional assumption in the universal wave function?

Yes.

 

[fanieh]

Yes.

Any reference? You mean the orthodox QFT can be interpretated as MWI since the difference is only all branches exist?

To a certain extent it can, but not in the ontological sense

What do you mean in the "ontological sense"? In the nothing happens in many world papers you guys discussed years back. You didn't give details (confirm or deny) how the interaction Hamiltonian can create position basis in the universal wave function. Are you saying there is no way to be sure because we can't solve the Hamiltonian of interacting objects (environment, subsystems)? I just want to know now what is the case as I want to go back to studying MWI. I think the position basis in BM is only temporary or preferred because of something. Remove that something and it's back to a formless MWI. Can the following be true?

In the Beginning, there is no basis of any kind.. there is simply the universal wave function of MWI where nothing happens..
Then position preferred basis is chosen..
Then the laws of physics came to be..

Yes.

 

[Demystifier]

You mean the orthodox QFT can be interpretated as MWI since the difference is only all branches exist?

Yes.

What do you mean in the "ontological sense"? In the nothing happens in many world papers you guys discussed years back. You didn't give details (confirm or deny) how the interaction Hamiltonian can create position basis in the universal wave function. Are you saying there is no way to be sure because we can't solve the Hamiltonian of interacting objects (environment, subsystems)? I just want to know now what is the case as I want to go back to studying MWI. I think the position basis in BM is only temporary or preferred because of something. Remove that something and it's back to a formless MWI. Can the following be true?

If you want to study MWI and questions like this, I would suggest you to first study the theory of decoherence, preferably from the book by Schlosshauer.

 

[fanieh]

Yes.If you want to study MWI and questions like this, I would suggest you to first study the theory of decoherence, preferably from the book by Schlosshauer.

I have read the Schlosshauer book cover to cover. I wanted to ask you this so let me ask now.
Is it possible in the beginning. it's really MWI.. then a force of nature (5th force) chooses the position preferred basis and turn it into BM?? .

 

[Demystifier]

I have read the Schlosshauer book cover to cover. I wanted to ask you this so let me ask now.
Is it possible in the beginning. it's really MWI.. then a force of nature (5th force) chooses the position preferred basis and turn it into BM?? .

http://fqxi.org/data/essay-contest-files/Nikolic_ultimate.pdf

 

[Demystifier]

@fanieh you are so fast in making questions. Do you ever try to answer them by yourself?

 

[fanieh]

@fanieh you are so fast in making questions. Do you ever try to answer them by yourself?

Ive been thinking of this for months. Schlosshauer only mentioned about the theme about "nothing happens in many worlds" indirectly only in 2 pages.. in page 337 "Everett Branches and the Preferred-Basis Problem". The book doesn't mention at all how the initial environment and system got decomposed in MWI. It didn't mention about the Factorization problem. It is only in PF archives that I can read about it.

Anyway. You sure there is no fatal flaw in the concept that a 5th fundamental force created the position preferred basis in MWI to become BM. Well. I'd lecture this to thousand of students so hope it's not illogical or false.. lol.. thanks..

 

[fanieh]

Oh. I wrote the reply before I saw you asked it.. Again..

Schlosshauer only mentioned about the theme about "nothing happens in many worlds" indirectly only in 2 pages.. in page 337 "Everett Branches and the Preferred-Basis Problem". The book doesn't mention at all how the initial environment and system got decomposed in MWI. It didn't mention about the Factorization problem. It is only in PF archives that I can read about it.

Anyway. You sure there is no fatal flaw in the concept that a 5th fundamental force created the position preferred basis in MWI to become BM. Well. I'd lecture this to thousand of students so hope it's not illogical or false.. lol.. thanks..

The Schlosshauer book didn't mention about the Factorization Problem that's why I was kinda confused about it. Well.. the mere fact our universe has environment and system splitted in the Big Bang means there is already position chosen.. and it doesn't mean there is BM, right? so it appears BM is just alternative way of looking at it or addition to preferred basis chosen in the initial environment-system decomposition isn't it? Schlosshaer nearly talked about this when he mentioned Stapp paper in page 337.. but he stopped short and so readers would not be aware of the problem. That's why I'm confused about this.

 

[Demystifier]

Ive been thinking of this for months. Schlosshauer only mentioned about the theme about "nothing happens in many worlds" indirectly only in 2 pages.. in page 337 "Everett Branches and the Preferred-Basis Problem". The book doesn't mention at all how the initial environment and system got decomposed in MWI. It didn't mention about the Factorization problem. It is only in PF archives that I can read about it.

You can read https://arxiv.org/abs/1703.08341 Sec. 3.3 Refs. [22,23,24].