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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)

#141

Post by layer8 »

_0w8t wrote: post #133
lmm wrote: post #118

Earlier quoted context omitted.

> This notion does not explain how the thermal bath appears. The point of the bath is it's a generic model of a large system with lots of states and interactions. > I.e. why the system interacts with a particular bath and not a superposition of such baths? The bath can be in a superposition state at the start, that's fine. (Indeed the whole model would be pretty useless otherwise).

Again, models of decoherence assume existence of an external bath resembling classical state. By interacting with it the system becomes classical itself if it is and the bath is sufficiently big. But it does not explain how that external bath appears. In universe-as-a-wave-function there is no external bath. The system as whole is always coherent and is described by a single wave function. Then the idea of the decohe…

I don’t think it’s black & white, either coherent or decoherent, for subsystems. It’s rather a scale. In that sense there may not be discrete “worlds”, but rather a continuum of them, matching the degree to which particles are entangled or not entangled, and in superposition or not in superposition.

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

#142

Post by dekhn »

lacasito25 wrote: post #125
dekhn wrote: post #24

The right frame of mind is not "shut up and calculate", it's "shut up and make testable hypotheses and then invalidate them experimentally".

But what if "make testable hypotheses and then invalidate them experimentally" is wrong to begin with?

that is a metascientific process (IE, questioning whether the scientific process is applicable), and outside the scope of exploration of QM, until somebody manages to demonstrate (in which case, I am truly interested in seeing what the alternative is... some sort of spooky mysticism?)

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

#143

Post by goatlover »

DiogenesKynikos wrote: post #110
goatlover wrote: post #92

Earlier quoted context omitted.

QM isn’t a complete description of the universe because of gravity, dark energy, dark matter, the arrow of time, and it doesn’t explain probability. So it’s a little premature to say that’s how the universe works.

Gravity, dark energy, dark matter or the arrow of time in no way conflict with QM. There isn't yet any successful quantum theory of gravity, but it's universally believed in the physics community that there will eventually be a quantum description of gravity. Dark energy and dark matter are merely components of the universe whose precise character is not yet known, but again, everyone believes that whatever they are,…

I don't see why that has to be the case other than mathematically it looks like QM "infects" everything as the theory stands now. But nature doesn't have to play along. Also, I forgot about spacetime. Is it quantum mechanical, relativistic or something else? And saying the universe began at al low entropy doesn't explain why it started out in that state.

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

#144

Post by goatlover »

lmm wrote: post #88
goatlover wrote: post #56

Earlier quoted context omitted.

But we only observe the cat being alive or dead. Where is the other cat? Are the many worlds hiding in the equation?

The other cat is being observed by the other you. When you open the box and look, you entangle your state with the cat's, and the wavefunction describing both of you becomes one that could be decomposed as a superposition of two "worlds", one with a live cat and a you who's observed a live cat, the other with a dead cat and a you who's observed a dead cat. As far as I can see people's objection to this tends to be th…

But the other me isn't observed. There's no empirical evidence for that other world. It's an interpretation of the mathematical formalism that there would be other mes making different observations. But there's nothing observational saying I have to choose the MWI interpretation as the correct one.

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

#145

Post by goatlover »

criddell wrote: post #138
goatlover wrote: post #89

Earlier quoted context omitted.

No, the common assumption is that we attempt to describe the universe with precise tools like mathematics, but the map isn’t the territory and all models are incomplete, some are just less incomplete. The universe being mathematical is a form of Platonism, which is the belief that mathematical and abstract objects are real.

> mathematical and abstract objects are real It might be a distinction without a difference, but I always understood the idea to be that objects we believe to be real are actually mathematical structures. I see it as sharing some ideas from the we-are-living-in-a-simulation idea. If we were in a simulation, you wouldn’t say data structures and objects are real but would say the table in front of you is actually just…

You would say the table in front of me is data inside a physical computer, whatever the physics of the real world were, assuming they aren't the same as our simulated world (perhaps they are an approximation of the real all depending on the purpose of the simulation).

That's different from the world being mathematical or informational, which raises the question of what makes it real to us. What breathes life into the equations? Consciousness? Where does consciousness come into the picture?

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

#146

Post by DiogenesKynikos »

goatlover wrote: post #143
DiogenesKynikos wrote: post #110

Earlier quoted context omitted.

Gravity, dark energy, dark matter or the arrow of time in no way conflict with QM. There isn't yet any successful quantum theory of gravity, but it's universally believed in the physics community that there will eventually be a quantum description of gravity. Dark energy and dark matter are merely components of the universe whose precise character is not yet known, but again, everyone believes that whatever they are,…

I don't see why that has to be the case other than mathematically it looks like QM "infects" everything as the theory stands now. But nature doesn't have to play along. Also, I forgot about spacetime. Is it quantum mechanical, relativistic or something else? And saying the universe began at al low entropy doesn't explain why it started out in that state.

You cannot construct a logical theory of physics in which some aspects of physics are quantum and others aren't. That's what I mean by Quantum Mechanics infecting the rest of physics.

This is why after the discovery of Quantum Mechanics, there was a drive to formulate quantum versions of all fundamental theories.

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

#147

Post by baja_blast »

superposeur wrote: post #137

This reads to me as a cogent defense of one particular interpretation: Everett. All is clear and logical except the part where Aaronson endorses the opinion that Everett isn’t wrong, but grandiose (whatever this means). In justification, it seems he is pushed into further twisted locutions. He speaks of what “breathes fire” into branches of the wave function and says that the question of existence of other branches i…

I feel like Everett is a way of trying to fit quantum mechanics with the block universe concept i.e. the past and future exist simultaneously.

But I like the idea proposed by Swiss physicist Nicolas Gisin who reasoned that when you our universe is finite and inherently imprecise that “time really passes and new information is created.” which fits with having to update after quantum collapse because new information has been introduced.

https://www.quantamagazine.org/does-time-really-flow-new-clu...

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

#150

Post by still_grokking »

Eupraxias wrote: post #97
dools wrote: post #68

Earlier quoted context omitted.

> what in your personal aesthetic tastes is making atoms more palatable? It’s pretty easy for me to imagine things bumping into each other because I see that happening all around me

All of this makes more sense when understood in terms of Field theory: David Tong: Quantum Fields https://youtu.be/zNVQfWC_evg?t=1168 "All the electrons that are in your body are not fundamental. All the electrons that exist in your body are waves of the same underlying field." The next question is, if there are no individual things, what does math count? http://www.katabane.com/mt/ontology.html

Differences.

You can only measure (compare) something in relation to something else.

If everything is homogeneous there are no measures, no clocks, and no way you could count anything.

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