A Bohm-type Theory may be necessary?

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Discussion Overview

The discussion centers on the implications of Bohm-type theories in understanding wave function collapse, particularly in relation to the behavior of photons over vast distances and the concept of instantaneous collapse. Participants explore the challenges of explaining these phenomena within the framework of quantum mechanics, touching on concepts such as causality, the nature of wave functions, and alternative theories like Relational Blockworld (RBW).

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • One participant questions how a wave function can collapse instantly over large distances and suggests that Bohm Theory's notion of a photon knowing its destination at departure could resolve this issue.
  • Another participant points out that instantaneous solutions may face challenges due to the lack of a future context, implying that backward causality might avoid this problem.
  • A participant introduces Relational Blockworld (RBW) as a potential alternative to Bohm's theory, suggesting that it offers a different perspective on motion and existence.
  • Concerns are raised about the implications of redshift in the Cosmic Microwave Background Radiation (CMB) and how it relates to the reality of wave functions and their properties before measurement.
  • One participant asserts that all equations must be dynamic, questioning the validity of instantaneous equations in the context of the discussion.
  • Another participant emphasizes the importance of relativity in discussing cosmological redshifts and how it relates to the behavior of wave functions over time.
  • There is a discussion about the temperature of the CMB at the time of last scattering and its implications for understanding the wave function as it travels through space.

Areas of Agreement / Disagreement

Participants express a range of views on the nature of wave function collapse and the validity of Bohm-type theories. There is no consensus on the best approach to understanding these phenomena, and multiple competing perspectives remain present throughout the discussion.

Contextual Notes

The discussion includes various assumptions about the nature of wave functions, causality, and the implications of relativity. Some participants express uncertainty regarding the definitions and implications of key concepts, such as the reality of wave functions and the mechanisms behind redshift.

p764rds
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I have always had trouble wondering how the cosmos can spread out a single photon wave function over millions of square miles - until it is decohered - and then the wave function collapses over that whole area including the one point at which it was 'observed'.

Why does this appear like a difficult task for the universe to achieve? Because of the huge spatial extent that the wave function needs to collapse instantly. What mechanism can collapse the wave function instantly over a large spatial area. Seems wrong to me.

So I am interested how Bohm Theory violates weak causality involving a reference frame that travels faster than light (backwards in time) such that the photon 'knows' its destination at point of departure. This is allowable because between photon spawning and observation no 'track' exists. It essentially travels along no knowable path. This has been shown by many experiments.

If a particle knows its point of arrival on its departure then the huge surface area of possible end points is no longer a huge problem for the Universe to solve. It 'knows' its arrival point at the start.

This would also restore some logic and rationality into bizarre experiments such as Wheeler's delayed path experiment.

I do not agree with Bohms pilot wave, BUT the idea of destination information known at departure IMO is needed to explain experimental results and allow collapse of wave function instantly over massive spatial areas that occurs instantly.
Bohm has a mechanism for this - his faster than reference frame - and I see no problem if an informational explanation that essentially ignores the distance of separation is used.

What do you think?

The contributor who wrote a lot about Bohm is not in the forum at present, so can someone else pick up the baton?
 
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These are some great questions. I would point out that instantaneous solutions suffer from the fact that a future context may not yet have occurred which plays into things. The backwards causal type solutions do not have that particular problem.
 
p764rds said:
What do you think?

I think that it’s very interesting. One way to escape Mr. Bohm is to use Relational Blockworld (RBW), where nothing really "moves", but I think someone else has to give you the details (I’m still working on it).

One question that I think is interesting is the redshift of the Cosmic Microwave Background Radiation (CMB).

If the wavefunction is not real, how do you 'stretch' something that does not exist!?

Or, as in the case of dBB, if the photon does not have a well-defined value of wavelength (before measurement), how do you 'stretch' something that is not well-defined!?

Just some thoughts...
 
There's no such thing as instantaneous equations, all equations have to be dynamic, but to be frank I'm just book marking this so pinch of salt. :smile:
 
DevilsAvocado said:
I think that it’s very interesting. One way to escape Mr. Bohm is to use Relational Blockworld (RBW), where nothing really "moves", but I think someone else has to give you the details (I’m still working on it).

One question that I think is interesting is the redshift of the Cosmic Microwave Background Radiation (CMB).

If the wavefunction is not real, how do you 'stretch' something that does not exist!?

Or, as in the case of dBB, if the photon does not have a well-defined value of wavelength (before measurement), how do you 'stretch' something that is not well-defined!?

Just some thoughts...

Red shift CMB and gravitational bending etc are relativistic corrections rather than operating on the wavefunction itself.
 
Yeah I know, it’s hard to talk about cosmological redshifts without mentioning relativity.

But anyhow, the CMB temperature was about 3000 K at the "time of last scattering", and now it’s ~3 K. The photons/wavefunction hitting the CCD camera in WMAP has been traveling for ~13 billion years to produce this picture in the "final measurement":

600px-WMAP_2010.png


Are you saying that relativity makes it OK to "fiddle" with wavefunction without "disturbing" it?
 
DevilsAvocado said:
Yeah I know, it’s hard to talk about cosmological redshifts without mentioning relativity.

But anyhow, the CMB temperature was about 3000 K at the "time of last scattering", and now it’s ~3 K. The photons/wavefunction hitting the CCD camera in WMAP has been traveling for ~13 billion years to produce this picture in the "final measurement":

Its the clock at the observation co-ordinate that has changed compared to the clock at the spawn point.
 

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