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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

#11

Post by FascistsAreLame »

amelius wrote: post #8
menzoic wrote: post #4

Veritasium has a great video that explains the concept of parallel worlds vs wave collapse in a single world https://youtu.be/kTXTPe3wahc

Nice video. Now I wonder if God uses structurally shared data structures in his implementation of the world. I also wonder if there can be a kind of continuous description of branching that is more amenable to calculus than the discrete tree-like branching.

It’s a functional immutable universe clearly. We’ve kinda reached the point where the believability of this construct is being stretched though. Good attempt, but I’d try again.

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

#12

Post by thechao »

jonahbenton wrote: post #3

I don't know to what degree the metaphor is accurate but as a non-physicist I find thinking about quantum mechanical experiments easier if I think of them as running code on a vast decentralized computing infrastructure. The concept of "measurement" is just executing code on one node that populates local registers- "creating" not "measuring". Yes- by running code you are pulling on a reality fabric that we still know…

I’m just now teaching myself QM (20 years after school). I can tell you that in QM, seemingly innocuous phrases like “locality” have highly unintuitive, nonstandard meanings. I’m just now getting a glimpse at how amazingly fucking awful pop-sci QM articles are.

If you’re interested in QM, read “The Theoretical Minimum”; the second book gets into QM. There are video lectures of the same material that complement the series, we’ll.

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

#13

Post by jonahbenton »

thechao wrote: post #12
jonahbenton wrote: post #3

I don't know to what degree the metaphor is accurate but as a non-physicist I find thinking about quantum mechanical experiments easier if I think of them as running code on a vast decentralized computing infrastructure. The concept of "measurement" is just executing code on one node that populates local registers- "creating" not "measuring". Yes- by running code you are pulling on a reality fabric that we still know…

I’m just now teaching myself QM (20 years after school). I can tell you that in QM, seemingly innocuous phrases like “locality” have highly unintuitive, nonstandard meanings. I’m just now getting a glimpse at how amazingly fucking awful pop-sci QM articles are. If you’re interested in QM, read “The Theoretical Minimum”; the second book gets into QM. There are video lectures of the same material that complement the se…

Appreciate the reference, cheers.

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

#14

Post by ssivark »

jonahbenton wrote: post #3

I don't know to what degree the metaphor is accurate but as a non-physicist I find thinking about quantum mechanical experiments easier if I think of them as running code on a vast decentralized computing infrastructure. The concept of "measurement" is just executing code on one node that populates local registers- "creating" not "measuring". Yes- by running code you are pulling on a reality fabric that we still know…

This perspective is interesting and potentially valuable, but it must be emphasized that quantum mechanics has linear evolution and hence “no cloning”. That means, when the registers are quantum objects, there is no such thing as copying a value into a register — there is only one version of each object, and you’re always manipulating it directly. That’s one aspect which leads to very difficult questions when thinking of “creating” at local nodes — because it’s the same object/copy that’s accessed at different nodes by various observers — so how can we ensure consistency of observations?

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

#15

Post by ahelwer »

jonahbenton wrote: post #3

I don't know to what degree the metaphor is accurate but as a non-physicist I find thinking about quantum mechanical experiments easier if I think of them as running code on a vast decentralized computing infrastructure. The concept of "measurement" is just executing code on one node that populates local registers- "creating" not "measuring". Yes- by running code you are pulling on a reality fabric that we still know…

An alternative way to view measurement is that you're just entangling yourself with the quantum system, and are as much in superposition as the system itself.

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

#16

Post by devit »

bondarchuk wrote: post #6

The original Wigner's friend paradox: https://en.wikipedia.org/wiki/Wigner%27s_friend The paradox seems to rest on magical thinking about consciousness, and if one simply accepts that a conscious observer can be in a superposition like any other piece of matter, the paradox is resolved. And, from the article: For Wigner, this was an absurd conclusion. Instead, he believed that once the consciousness of an observer be…

It indeed seems so, i.e. that there is no paradox in the many-worlds and possibly other interpretations (as a non-expert in quantum physics).

How did they manage to get the paper accepted in the (supposedly selective) Nature Physics journal though? Is there something we are missing?

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

#17

Post by squibbles »

bondarchuk wrote: post #6

The original Wigner's friend paradox: https://en.wikipedia.org/wiki/Wigner%27s_friend The paradox seems to rest on magical thinking about consciousness, and if one simply accepts that a conscious observer can be in a superposition like any other piece of matter, the paradox is resolved. And, from the article: For Wigner, this was an absurd conclusion. Instead, he believed that once the consciousness of an observer be…

Translating the thought experiment to an actual physical experiment is something worth appreciating.

A possible lack of absoluteness of observed events has implications for what observations may or may not be reconcilable using existing scientific methods.

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

#18

Post by scythmic_waves »

TheOtherHobbes wrote: post #7
bondarchuk wrote: post #6

The original Wigner's friend paradox: https://en.wikipedia.org/wiki/Wigner%27s_friend The paradox seems to rest on magical thinking about consciousness, and if one simply accepts that a conscious observer can be in a superposition like any other piece of matter, the paradox is resolved. And, from the article: For Wigner, this was an absurd conclusion. Instead, he believed that once the consciousness of an observer be…

You might consider reading the original paper. Because the experiment doesn't rely on conscious observers at all. (Unless you think photons are conscious, which I'm assuming you don't.)

> (Unless you think photons are conscious, which I'm assuming you don't.)

Well, panpsychism is a thing and is actually having a bit of a renaissance.

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

#19

Post by MrPatan »

devit wrote: post #16
bondarchuk wrote: post #6

The original Wigner's friend paradox: https://en.wikipedia.org/wiki/Wigner%27s_friend The paradox seems to rest on magical thinking about consciousness, and if one simply accepts that a conscious observer can be in a superposition like any other piece of matter, the paradox is resolved. And, from the article: For Wigner, this was an absurd conclusion. Instead, he believed that once the consciousness of an observer be…

It indeed seems so, i.e. that there is no paradox in the many-worlds and possibly other interpretations (as a non-expert in quantum physics). How did they manage to get the paper accepted in the (supposedly selective) Nature Physics journal though? Is there something we are missing?

You're not missing anything. Maybe just the last step of lowering your opinion of the journal.

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

#20

Post by canjobear »

bondarchuk wrote: post #6

The original Wigner's friend paradox: https://en.wikipedia.org/wiki/Wigner%27s_friend The paradox seems to rest on magical thinking about consciousness, and if one simply accepts that a conscious observer can be in a superposition like any other piece of matter, the paradox is resolved. And, from the article: For Wigner, this was an absurd conclusion. Instead, he believed that once the consciousness of an observer be…

> if one simply accepts that a conscious observer can be in a superposition like any other piece of matter, the paradox is resolved.

It’s not so simple. Suppose you’re in a box and observe a quantum experiment, and then I open the box and observe you. Then before I open the box you’re in a superposed state |x> + |y>, corresponding to the two possible outcomes x and y. Fine, no problem so far. But what is your own subjective experience? You, subjectively, inside the box, will only ever observe yourself to be in |x> or |y>, never |x> + |y>. Even if from the outside your brain can be said to be in a superposed state, your experience of the world is not superposed.

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