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The Zen anti-interpretation of quantum mechanics (2021)

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Re: The Zen anti-interpretation of quantum mechanics (2021)

#41

Post by Jensson »

DiogenesKynikos wrote: post #37
goatlover wrote: post #31

Earlier quoted context omitted.

So you’re endorsing Many Worlds with an appeal to the anthropic principle. That’s fine, but you do have to assume MWI is the true interpretation of the mathematical formalism.

The Many-Worlds Interpretation is not really an interpretation. It just says that the known laws of Quantum Mechanics are correct, and that any measurement process itself has to obey the laws of Quantum Mechanics. In other words, nothing un-Quantum-Mechanical happens during measurement.

MVI doesn't solve wave function collapses, if it did it would be able to tell exactly when the universe will split into many worlds, but it can't. So it doesn't solve anything, the difficulty with the theory is still there.

Re: The Zen anti-interpretation of quantum mechanics (2021)

#42

Post by TheRealPomax »

_0w8t wrote: post #27
FeepingCreature wrote: post #17

Earlier quoted context omitted.

In the single wavefunction, beings who perceive classical reality arise from mere wavefunction mathematics. How does this not answer the question? Once you can locate yourself in a system, the system is adequate as a physical theory of your phenomenological state.

This does not explain how a classical observer gets probabilities that are precisely measured. In universe-as-a-wave-function there are no probabilities. So how exactly do they arise and what they mean?

probabilities are, by definition, not precisely measured. "Real world" probabilities are derived from imprecise measurements, and model probabilities are dictated by (simplified) model constraints.

Re: The Zen anti-interpretation of quantum mechanics (2021)

#43

Post by scottmsul »

Something that's always bothered me about many-worlds is that it states the number of worlds should always be increasing exponentially. Which means from an anthropic point of view, the most likely time to be born is the last ever human, with insanely exponential odds. But many people have been born in my lifetime, ergo many-worlds seems unlikely.

Re: The Zen anti-interpretation of quantum mechanics (2021)

#44

Post by layer8 »

Jensson wrote: post #41
DiogenesKynikos wrote: post #37

Earlier quoted context omitted.

The Many-Worlds Interpretation is not really an interpretation. It just says that the known laws of Quantum Mechanics are correct, and that any measurement process itself has to obey the laws of Quantum Mechanics. In other words, nothing un-Quantum-Mechanical happens during measurement.

MVI doesn't solve wave function collapses, if it did it would be able to tell exactly when the universe will split into many worlds, but it can't. So it doesn't solve anything, the difficulty with the theory is still there.

The perceived wave function collapse is explained by decoherence. There is no extra “split” that happens. “World” is just a term referring to the parts of the universal wave function that are entangled with each other.

As to “exactly when the universe will split into many worlds”, it happens zillions of times per second pretty much everywhere. It’s even not clear whether the branching is a discrete and countable occurrence, it could really be a continuous fanning out.

Re: The Zen anti-interpretation of quantum mechanics (2021)

#45

Post by mathgenius »

I like the many-interpretations interpretation of quantum. It says that you should believe all of them, or rather, choose a different interpretation based on your mood. For the optimistic, it's many-worlds. If you are going out tonight & hoping to get lucky, it better be Copenhagen. If you are falling into despair then it's going to be superdeterminism for you.

Re: The Zen anti-interpretation of quantum mechanics (2021)

#46

Post by russdill »

Jensson wrote: post #41
DiogenesKynikos wrote: post #37

Earlier quoted context omitted.

The Many-Worlds Interpretation is not really an interpretation. It just says that the known laws of Quantum Mechanics are correct, and that any measurement process itself has to obey the laws of Quantum Mechanics. In other words, nothing un-Quantum-Mechanical happens during measurement.

MVI doesn't solve wave function collapses, if it did it would be able to tell exactly when the universe will split into many worlds, but it can't. So it doesn't solve anything, the difficulty with the theory is still there.

There isn't some physical event in MWI that splits worlds. It's just a consequence of decoherence.

Re: The Zen anti-interpretation of quantum mechanics (2021)

#47

Post by consilient »

scottmsul wrote: post #43

Something that's always bothered me about many-worlds is that it states the number of worlds should always be increasing exponentially. Which means from an anthropic point of view, the most likely time to be born is the last ever human, with insanely exponential odds. But many people have been born in my lifetime, ergo many-worlds seems unlikely.

The many-worlds interpretation is badly named: the "worlds" are just particularly classical-looking regions of the wavefunction we've chosen to draw some lines around for our own convenience. They're part of the map, not the territory.

It's true that a decohering system will have exponentially more classical-ish parts over time - but the parts get smaller at the same rate, and the total size of the system remains the same.

Re: The Zen anti-interpretation of quantum mechanics (2021)

#48

Post by kbelder »

scottmsul wrote: post #43

Something that's always bothered me about many-worlds is that it states the number of worlds should always be increasing exponentially. Which means from an anthropic point of view, the most likely time to be born is the last ever human, with insanely exponential odds. But many people have been born in my lifetime, ergo many-worlds seems unlikely.

Does that argument hold for all of us?

Re: The Zen anti-interpretation of quantum mechanics (2021)

#49

Post by Jensson »

layer8 wrote: post #44
Jensson wrote: post #41

Earlier quoted context omitted.

MVI doesn't solve wave function collapses, if it did it would be able to tell exactly when the universe will split into many worlds, but it can't. So it doesn't solve anything, the difficulty with the theory is still there.

The perceived wave function collapse is explained by decoherence. There is no extra “split” that happens. “World” is just a term referring to the parts of the universal wave function that are entangled with each other. As to “exactly when the universe will split into many worlds”, it happens zillions of times per second pretty much everywhere. It’s even not clear whether the branching is a discrete and countable occu…

So when does decoherence happen? Provide a formula for it. That is what people struggle with in quantum mechanics, MWI just deflects the question. Without a formula for when this phenomena happens any "interpretation" is just nonsense, except as a tool to get towards that formula.

Re: The Zen anti-interpretation of quantum mechanics (2021)

#50

Post by russdill »

Jensson wrote: post #49
layer8 wrote: post #44

Earlier quoted context omitted.

The perceived wave function collapse is explained by decoherence. There is no extra “split” that happens. “World” is just a term referring to the parts of the universal wave function that are entangled with each other. As to “exactly when the universe will split into many worlds”, it happens zillions of times per second pretty much everywhere. It’s even not clear whether the branching is a discrete and countable occu…

So when does decoherence happen? Provide a formula for it. That is what people struggle with in quantum mechanics, MWI just deflects the question. Without a formula for when this phenomena happens any "interpretation" is just nonsense, except as a tool to get towards that formula.

There's no yes/no equation as decoherence is statistical in nature.
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