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Physicists found a new quantum paradox that casts doubt on a pillar of reality

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Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#61

Post by Zenbit_UX »

Whenever I hear about weird shit from the realm of quantum physics (this theory, double-slit, etc..) I can't help but think:

Why would I hardcode values for imperceptible objects, that would take an enormous about of ram and cpu time to constantly update values in the off chance it's needed.

Much more efficient to optimize for what the _player_ can see at their perspective. Oh and I should probably code in some error handling in the fluke event one of these particles is detected, I'll just calculate their position retroactively, the user will never be able to tell and we can host way more players due to the reduced memory.

It would seem to me that god is a junior dev and no one reviewed his pull requests.

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#62

Post by rantwasp »

this is not convincing at all. we pretend that we can have perfectly isolated quantum systems (a particle, a few particles) and we can reason about and extrapolate the findings. we cannot have isolated particles - they can be regarded as isolated for experimental purposes but the reality is that probably the whole universe is a massive wave function that encompasses everything and we can approximate in some really special cases (ie system above).

we also pretend that consciousness is something special and altering the state a somewhat complicated wetware had consequences on “reality”. it doesn’t.

the measurement problem is an extremely good example of how we think. a measurement does not make sense to a cow. it’s abstract. we made it up. we have conventions that help make it useful, but those conventions break down when our senses (or things we use to amplify out senses) cannot measure what we want to measure.

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#63

Post by tsimionescu »

undreren wrote: post #56
phkahler wrote: post #28

Earlier quoted context omitted.

Or if you embrace nonlocality.

Wouldn’t that imply FTL travel, at least for information?

No, non-locality simply means that effects happen at infinite speeds, not that they carry information.

For example, the Copenhagen interpretation of QM abandons both locality and realism - particles don't have definite states, and they also communicate at infinite speed (but in a way that can't carry information).

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#64

Post by colordrops »

Based on my very limited understanding it seems that anything that interacts with a system can be treated as an "observer", and thus a chain of observations can occur as one particle interacts with the next, enlarging the system that is in superposition for the next observer.

Do physicists axiomatically treat a "conscious observer" as an atomic unit? It seems the case based on neurological and psychological research that the mind is actually not a single unit but many units working together, and the sense of a singular self is an illusion, which would correlate with the fact that we are made up of a conglomeration of atoms and systems made of these atoms.

When we say that a person is observing a quantum system, could this actually be a cascade of observations of various parts of the mind rather than a singular event, since the mind is not monolithic?

On a side note (and perhaps unrelated), if different parts of the brain/mind could be in different quantum states, could this be a factor in how the mind operates?

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#65

Post by Strilanc »

lisper wrote: post #55
adrianN wrote: post #37

Earlier quoted context omitted.

I'm not convinced that intelligence requires copying information in the way that the no-cloning theorem forbids. Approximate cloning is not forbidden for example.

The problem is not copying internal states, the problem is I/O. A given instance of a quantum computation can only be queried once before it decoheres and goes "poof" because the querying process itself decoheres the system. So a quantum computer can never pass the Turing test because it cannot even participate in the Turing test without destroying itself.

Requiring the the quantum algorithm have literally no interaction with the outside world to count as quantum is a strawman.

An AI could use Grover search when trying to find a good enough response. That would be like part of the AI going into and out of superposition for an efficiency boost.

Many quantum tasks are more efficient if certain catalyst states are present [1][2]. That would be like a part of the AI staying permanently in superposition while still ultimately contributing to classical results, again for an efficiency boost.

1: https://en.wikipedia.org/wiki/Quantum_catalyst

2: https://arxiv.org/abs/1812.01238

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#66

Post by rantwasp »

Zenbit_UX wrote: post #61

Whenever I hear about weird shit from the realm of quantum physics (this theory, double-slit, etc..) I can't help but think: Why would I hardcode values for imperceptible objects, that would take an enormous about of ram and cpu time to constantly update values in the off chance it's needed. Much more efficient to optimize for what the _player_ can see at their perspective. Oh and I should probably code in some error…

disagree on the junior dev part and on the god part.

what you’re describing is called “simulation theory” and it has been proposed and discussed at length

i think lazy evaluation makes sense in that context. i also think that having a few basic rules and after that applying them consistently across your simulation space make sense. if your basic space unit of reality is way smaller than the sims in it can perceive and measure they’re gonna start making stuff up

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#67

Post by sgillen »

Zenbit_UX wrote: post #61

Whenever I hear about weird shit from the realm of quantum physics (this theory, double-slit, etc..) I can't help but think: Why would I hardcode values for imperceptible objects, that would take an enormous about of ram and cpu time to constantly update values in the off chance it's needed. Much more efficient to optimize for what the _player_ can see at their perspective. Oh and I should probably code in some error…

One problem with this view is that “unobserved” particles still take up a large (possibly larger?) amount of computation. Rather than being in one position, it acts like a wave, being a little bit in every possible allowable position. These probability waves also interact with each other (which is what the double slit experiment demonstrates).

That being said if it was demonstrated that un collapsed wave functions are somehow more efficient to calculate that would definitely give credence to the simulation hypothesis.

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#68

Post by webmaven »

lisper wrote: post #55
adrianN wrote: post #37

Earlier quoted context omitted.

I'm not convinced that intelligence requires copying information in the way that the no-cloning theorem forbids. Approximate cloning is not forbidden for example.

The problem is not copying internal states, the problem is I/O. A given instance of a quantum computation can only be queried once before it decoheres and goes "poof" because the querying process itself decoheres the system. So a quantum computer can never pass the Turing test because it cannot even participate in the Turing test without destroying itself.

> The problem is not copying internal states, the problem is I/O. A given instance of a quantum computation can only be queried once before it decoheres and goes "poof" because the querying process itself decoheres the system. So a quantum computer can never pass the Turing test because it cannot even participate in the Turing test without destroying itself.

You seem to be saying that a computer can only be called a quantum computer if it never decoheres. Or perhaps that it is only usable in some sort of batch-mode, like mainframes with punch-card decks, with each calculation cycle being a laborious one-shot affair.

I have little doubt that many near-future quantum computers will be used in exactly that mode, but also that at some point thereafter their coherence/decoherence cycles will start to be measured in Hz, Khz, etc.

Therefore there should in principle be no barrier to a quantum computer participating in a Turing test, or any other use-case that requires interaction.

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#69

Post by stared »

Have it ever happened o you that you read "a pillar of reality" and it turned out to be more than a clickbait?

Me neither.

(To make it clear: the content is interesting, even if clearly for popular science audience (some statements about physics are false, e.g. "These are all intuitive ideas, and widely believed even by physicists." The title is worth a tabloid.)

Re: Physicists found a new quantum paradox that casts doubt on a pillar of reality

#70

Post by canjobear »

undreren wrote: post #56
phkahler wrote: post #28

Earlier quoted context omitted.

Or if you embrace nonlocality.

Wouldn’t that imply FTL travel, at least for information?

Nonlocality basically means that the universe has a global RNG state. If you write some code that uses a global RNG and no other global variables, that code will still be "local" in the sense that functions cannot communicate information between each other using the RNG. But the outcomes of the functions might still be correlated in interesting ways (corresponding to entanglement).
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