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Physicists provide support for retrocausal quantum theory

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Re: Physicists provide support for retrocausal quantum theory

#91

Post by gnaritas »

ridewinter wrote: post #56
ethn wrote: post #48

Earlier quoted context omitted.

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.

> Many-worlds has a concrete, physical, simple explanation for quantum effects.

So does religion, it doesn't make it true without evidence. Inventing unseen universes is easy, it's not simple, it fails the Occam's razor test for the same reason gods do.

Re: Physicists provide support for retrocausal quantum theory

#92

Post by gnaritas »

mikeash wrote: post #65
ridewinter wrote: post #44

Earlier quoted context omitted.

Math is used to explain the universe. It isn't an explanation in of itself. We never progressed anywhere by saying "something just works" and leaving it at that. Challenge yourself.

Seems like it's the opposite to me. We never progressed anywhere with "explanations." Progress comes when those explanations are condensed to testable mathematics. I'm curious as to what you think consists of "an explanation" that's more useful than mathematics. Let's take a simple classical phenomenon to keep it easy, such as kinetic energy. The mathematical statement is E_k = 1/2 m v^2. What non-math explanation wo…

Maths are models of reality which may or may not be correct and can only be verified by comparing them to reality. While they serve as the most simple way to explain reality, don't confuse them with reality. The map is not the territory.

Re: Physicists provide support for retrocausal quantum theory

#93

Post by millstone »

yorwba wrote: post #59
raverbashing wrote: post #54

Earlier quoted context omitted.

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.

All quantum mechanics has notions of "points in space that support the wavefunction," but these are different from the "worlds" in MWI.

Re: Physicists provide support for retrocausal quantum theory

#94

Post by Tenoke »

nilson wrote: post #83
ridewinter wrote: post #15

The many-worlds interpretation of quantum mechanics is the only one that's easy to understand. All others seem to bend over backwards to realistically explain quantum effects. It's so rare to find clear explanations, but they do exist. My favorite from David Deutsch, a main creator of the idea of quantum computing: To those who still cling to a single-universe world-view, I issue this challenge: explain how Shor’s al…

im not "clinging to single universe world view" but i got 2 questions: 1. has this alghoritm actually been executed somewhere? 2. does this mean there is infinite storage posibillity to store any data you want or it must be "special" data. and how much time does it take to access any segment of this data. if the answer is no to both question then my answer is: "it doesn't work."

> 1. has this alghoritm actually been executed somewhere?

Yeah, but so far we have the highest factorization achieved is 21 because we've only built relatively tiny quantum computers.[0]

0. https://en.wikipedia.org/wiki/Shor%27s_algorithm

Re: Physicists provide support for retrocausal quantum theory

#95

Post by nol13 »

ridewinter wrote: post #15

The many-worlds interpretation of quantum mechanics is the only one that's easy to understand. All others seem to bend over backwards to realistically explain quantum effects. It's so rare to find clear explanations, but they do exist. My favorite from David Deutsch, a main creator of the idea of quantum computing: To those who still cling to a single-universe world-view, I issue this challenge: explain how Shor’s al…

Not clinging to single universe rule, but multiworld is a big leap, plus seems weird. Still significantly less of a leap than single-world narrative of "two particles have some probability to do something > ????!?? > they did this" so I dunno. Can MWI derive the born rule yet? Either way neither seems likely.

Thus my hypothesis that the correct number of worlds is actually a fractal.

Re: Physicists provide support for retrocausal quantum theory

#96

Post by Simon_says »

mikeash wrote: post #82
clock_tower wrote: post #81

Earlier quoted context omitted.

> Our brains aren't evolved for understanding the true nature of the universe, they're evolved for reproducing and surviving in a very simple world. Absolutely. For survival-to-reproduction -- and for quite a bit more than that -- Aristotle's physics are enough; but they're full of absurdities and strange edge cases when you look at them more carefully. To explain the flight of an arrow, you need Newton... and then y…

Feynman said, "I think I can safely say that nobody understands quantum mechanics." This is a guy who won the Nobel Prize for work in quantum mechanics. QM does not line up with human intuition at all. It looks like this is a fundamental issue with how the universe works, not a problem with our explanations. And really, that shouldn't be any surprise. There's no reason to expect the universe's workings to match our i…

Feynman said that quote in 1965, and it may have been true when he said it. The Many-Worlds Interpretation was technically invented before then (1957), but was a fringe theory and not disseminated much prior to the 1980s. I don't think you could get away with saying the same quote today.

Re: Physicists provide support for retrocausal quantum theory

#97

Post by Simon_says »

BoiledCabbage wrote: post #70
ridewinter wrote: post #50

Earlier quoted context omitted.

That's exactly what I'm saying! All other explanations say something confusing and obfuscating like "there are no photons". Many-worlds keeps it simple and says "there are photons, and the reason they behave like that is because they're interacting with parallel universes". You can't explain why they behave like that, so you say that the photon isn't really real, and have a complicated explanation of it.

Clearly this is all subjective, but Pilot Wave theory (De Broglie & Bohm) is the simplest least "crazy" of all the explanations. Horribly simplified: Space isn't empty, there is an "ether". Matter moving through the ether interacts with it and produces waves just like a very light boat in a lake - these crests and troughs exactly line up with the magical waveform. All of the quantum behavior we see is explained by th…

The Pilot Wave Interpretation is one of the strangest contortions I've ever seen. You go to all the trouble to set up the wave equation acting on phase space of the entire universe, but then you remember that you think particles are fundamental elements of reality, so you drop them in and say they're guided by your wave equation.

If you take Pilot Wave Interpretation and just take out the particles, you're left with the Many Worlds Interpretation with exactly the same predictions. To paraphrase Netwon, there's no need for that hypothesis.

Re: Physicists provide support for retrocausal quantum theory

#98

Post by eridius »

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.

How is "a particle that interacts with particles in parallel universes" any simpler? That sounds like a crazy special rule. Why and how do individual photons/particles interact with parallel universes when nothing else can do so? Honestly, MWI sounds to me like just a fancy way of saying "magic".

Re: Physicists provide support for retrocausal quantum theory

#99

Post by naasking »

FeepingCreature wrote: post #9
naasking wrote: post #7

Earlier quoted context omitted.

> This would allow us to predict the future and potentially allow for time travel as well. It doesn't actually, they discuss this in the article. The laws of thermodynamics impose an arrow of time via boundary conditions, and something similar would apply here.

Purely as an amateur, it seems unelegant to have something that violates causality as a mechanism, but doesn't give you a way to violate cause and effect at a higher level. It's like the universe is conspiring to keep its awesome tricks from you.

> It's like the universe is conspiring to keep its awesome tricks from you.

Well that's just inevitable. You're never going to see a naked singularity, for instance.

Re: Physicists provide support for retrocausal quantum theory

#100

Post by yorwba »

millstone wrote: post #93
yorwba wrote: post #59

Earlier quoted context omitted.

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.

All quantum mechanics has notions of "points in space that support the wavefunction," but these are different from the "worlds" in MWI.

Seems like I have been misunderstanding MWI all the time. How are they different?
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