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Physicists provide support for retrocausal quantum theory

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Re: Physicists provide support for retrocausal quantum theory

#51

Post by ridewinter »

mikeash wrote: post #47
ridewinter wrote: post #33

Earlier quoted context omitted.

Explain the double slit experiment to me. The single photon somehow calculates the interference pattern with photons that don't exist, in our world at least. If there's not parallel universes, how does a single atom calculate that interference pattern? Where do those calculations occur? All other theories say it happens by magic and give all sorts of complicated non-real obfuscations to explain it.

The atom is a wave, which can interfere with itself.

I think Deutsch would say there isn't actually a wave-particle duality. That's just an obfuscation that doesn't have any reality to it. Many-worlds has a much simpler explanation - there is simply a particle that interacts with particles in parallel universes that produce a wave-like interference effect.

Re: Physicists provide support for retrocausal quantum theory

#52

Post by amoruso »

John Cramer has been pointing this out for years (since the 1980s I think):

"The Transactional Interpretation of Quantum Mechanics and Quantum Nonlocality"

https://arxiv.org/abs/1503.00039

Also, Bell's inequality shows the state vector is nonlocal, and and that implies causality violation in relativity.

Third, quantum information theory has retrocausality in the form of negative entropy:

"Negative entropy in quantum information theory"

https://arxiv.org/abs/quant-ph/9610005

Too many things pointing in the same direction. This is the right way to look at it.

Re: Physicists provide support for retrocausal quantum theory

#53

Post by ridewinter »

jerf wrote: post #45
raverbashing wrote: post #38

Earlier quoted context omitted.

Bohmian mechanics seems like a better explanation than "there are infinite universes out there"

Yes, I find the whole "Explain this in any other way!" sort of a bizarre demand. You've got your choice of 5 or 6 decent isomorphic explanations. Preference for "many worlds" seems to boil down to "it annoys my common sense less than some of the others", which is a very personal concern rather than a scientific one. Personally, I actually think retrocausality, once you twist your brain around it, is another perfectly…

It's more of a recognition that many-worlds actually has a physical basis to it, while the others talk about an obfuscated non-physical construction.

Re: Physicists provide support for retrocausal quantum theory

#54

Post by raverbashing »

ridewinter wrote: post #41
raverbashing wrote: post #38

Earlier quoted context omitted.

Bohmian mechanics seems like a better explanation than "there are infinite universes out there"

I'm sure you could confuse the heck out of me trying to explain it. Deutsch would say it's just a clever obfuscation of what's really happening. And his many-worlds explanation is so incredibly simple that my small mind uses Occam's razor to figure out what to believe.

As simple as using God to explain how the universe came to be

It's not about a simple explanation, it's about explaining using simple things.

A wave is simpler than "infinite worlds"

Re: Physicists provide support for retrocausal quantum theory

#55

Post by mikeash »

ridewinter wrote: post #51
mikeash wrote: post #47

Earlier quoted context omitted.

The atom is a wave, which can interfere with itself.

I think Deutsch would say there isn't actually a wave-particle duality. That's just an obfuscation that doesn't have any reality to it. Many-worlds has a much simpler explanation - there is simply a particle that interacts with particles in parallel universes that produce a wave-like interference effect.

He might say that, but so what? It's clear that he favors many-worlds, but that doesn't mean the rest of us have to. My point is that he's attempting to prove many-worlds by assuming that none of the other explanations are true, i.e. he's begging the question.

Re: Physicists provide support for retrocausal quantum theory

#56

Post by ridewinter »

ethn wrote: post #48
ridewinter wrote: post #39

Earlier quoted context omitted.

Take the interference pattern built in the famous double slit experiment: what Deutsch and other recognized is that there's computation happening to create that pattern. And similar computation is present in all quantum effects. Quantum computers in effect harness that natural computational power. I don't fully understand how, but Deutsch proved that you can create a general computing machine from those natural quant…

You continue to ignore the weak points of Deutsch's argument that I've pointed out. You can create a computing machine by assigning physical states to any physical behavior, quantum, classical, hamiltonian, etc. The proof is trivial and it is not a proof he came up with. It further follows, there is no computation happening during the creation of an interference pattern until we assign it our own abstract semantic st…

Many-worlds has a concrete, physical, simple explanation for quantum effects. The other interpretations are based in the abstract, and are incredibly difficult to understand. That's all I'm saying.

Re: Physicists provide support for retrocausal quantum theory

#57

Post by akvadrako »

raverbashing wrote: post #54
ridewinter wrote: post #41

Earlier quoted context omitted.

I'm sure you could confuse the heck out of me trying to explain it. Deutsch would say it's just a clever obfuscation of what's really happening. And his many-worlds explanation is so incredibly simple that my small mind uses Occam's razor to figure out what to believe.

As simple as using God to explain how the universe came to be It's not about a simple explanation, it's about explaining using simple things. A wave is simpler than "infinite worlds"

The wavefunction is exactly the same as "infinite worlds". The essential aspect of the Everett / many-worlds view is that the wavefunction is the complete description of reality.

The "worlds" are just approximate ways of slicing up the wavefunction which correspond to our sense of classical reality. They are clearly (and uncontroversially) identifiable if you run a simulation.

Re: Physicists provide support for retrocausal quantum theory

#58

Post by jerf »

ridewinter wrote: post #53
jerf wrote: post #45

Earlier quoted context omitted.

Yes, I find the whole "Explain this in any other way!" sort of a bizarre demand. You've got your choice of 5 or 6 decent isomorphic explanations. Preference for "many worlds" seems to boil down to "it annoys my common sense less than some of the others", which is a very personal concern rather than a scientific one. Personally, I actually think retrocausality, once you twist your brain around it, is another perfectly…

It's more of a recognition that many-worlds actually has a physical basis to it, while the others talk about an obfuscated non-physical construction.

"Many worlds has a physical basis to it" has no physics-meaning that I can discern. In order to have one, it would have to deviate from the other isomorphisms and cease to be an isomorphism, and thus somehow be testable, which it isn't. (My previous post is word salad to some extent too, since I'm jamming it into an HN post. But the core insight there is basically, let the math be the math and stop imposing your globally-based ideas on the local world.)

It would have a "physical basis" to it if you could visit the alternatives somehow, in which case they could be demonstrated to physically exist and all doubt would be removed. But so far that is not on offer.

Re: Physicists provide support for retrocausal quantum theory

#59

Post by yorwba »

raverbashing wrote: post #54
ridewinter wrote: post #41

Earlier quoted context omitted.

I'm sure you could confuse the heck out of me trying to explain it. Deutsch would say it's just a clever obfuscation of what's really happening. And his many-worlds explanation is so incredibly simple that my small mind uses Occam's razor to figure out what to believe.

As simple as using God to explain how the universe came to be It's not about a simple explanation, it's about explaining using simple things. A wave is simpler than "infinite worlds"

The "worlds" are just points in the space that supports the wave. You can use any other name, if you prefer, but there seem to be an infinite number of them.

Re: Physicists provide support for retrocausal quantum theory

#60

Post by [deleted] »

mirekrusin wrote: post #43
rf15 wrote: post #35

Earlier quoted context omitted.

don't remind me that people actually believe that you can infer the existence of a simulation only with data points that are created and controlled by it.

Simulation part was a joke. But the static, unchangeable past is interesting because: 1. assumption that the past is static and can't change is not crazy and if retrocausal influence exists, it could imply Many Worlds interpretation as more plausible - there must be at least 2 different universes with static past if you can choose at present past A or past B. The joke is that branching universes creates large overhea…

[deleted]
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