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Physicists Create World’s First Time Crystal

technologyreview.com

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Re: Physicists Create World’s First Time Crystal

#111

Post by radarsat1 »

ww520 wrote: post #39
radarsat1 wrote: post #24

Earlier quoted context omitted.

right, now i'll have to read the article to understand why there is no energy loss :) it does seem to be breaking some rules.. but I guess that's the achievement here. Intuitively there should be some concept of friction/heat loss but maybe on this scale things are different. Maybe it could be exploited as a battery? A way of capturing energy into a stable kinetic "state". (Like a flywheel..)

Moving doesn't implement energy loss automatically. When things are set in motion, they will continue to move infinitely unless interfered by outside forces.

Right, but physical movement within a material without loss due to friction implies some kind of mechanical superconductor.. I mean, that's a pretty cool concept.

Re: Physicists Create World’s First Time Crystal

#112

Post by lisper »

ttctciyf wrote: post #108
lisper wrote: post #77

Earlier quoted context omitted.

It's true. I'm not a physicist. I have never claimed to be a physicist. The only contribution I have ever claimed is a pedagogical one. When I first wrote the paper 15 years ago I submitted it to Physics Today. It was rejected, not because it was wrong, but because the reviewers thought that it was nothing new, that everyone already knew this stuff. Since then the physics community has bifurcated rather neatly into t…

Hi, I'm considerably less of a physicist than yourself :) I did watch your google talk video, and have to thank you for an interesting presentation that introduced me to a couple of new perspectives on quantum interpretation. I'm utterly unqualified to have an opinion on the topic, but enjoy thinking about it sometimes. So I just wanted to ask in respect of "no one has ever pointed out any actual mistakes" - have you…

I have not seen this particular exchange, but it is typical of people who have missed the point. Yes, of course the EPRG paradox doesn't work. That's the whole point. It's a straw man, designed to draw attention to the fact that there is something wrong with QM pedagogy.

The thing that people who critique my work generally miss is that it is not about physics, it's about pedagogy. It's about how the physics is explained. Everyone agrees on the physics. It's the explanation that is at issue. The whole first half of the talk is the problem statement.

(God damn this is annoying: "I'm afraid I won't have time to critique whatever it is he says in the second half of the video." Well, the second half is where I explain why the EPRG paradox doesn't actually work. By the time I gave that talk I already knew that people got this wrong, so I went to great lengths to highlight the fact that EPRG was a straw man. And then people jump into the middle of the video, see the story out of context, and say "This is wrong." Well, duh, of course it's wrong. That's the whole fucking point!)

Re: Physicists Create World’s First Time Crystal

#113

Post by lisper »

omginternets wrote: post #110
lisper wrote: post #45

Earlier quoted context omitted.

You're not that far off. The particles aren't really moving , i.e. they are not going from one spatial location to another. What is happening is that they are changing quantum spin states, and the spin states are changing in such a way that it appears that a circular arrangement of atoms is rotating. This is a reflection of the fact that an atom isn't really a thing (there are no "things", i.e. there are no particles…

Where does the "time" part come in?

Mainly in the marketing. If it were called "ground-state quantum resonance" (which is what it is) no one would care.

Re: Physicists Create World’s First Time Crystal

#114

Post by nickpsecurity »

lisper wrote: post #100
nickpsecurity wrote: post #96

Earlier quoted context omitted.

" And the answer is that when you do the math, the result of taking a subset of the wave function (the mathematical operation is called a "trace") is something that looks like a classical system." Your statement just connected to unrelated subjects in my head that might mean something. As I studied hardware, I found that underneath these nice, mathematical blocks that we build digital with are analog components that…

The difference between classical and quantum is not really analogous to the difference between digital and analog, it's the difference between real numbers and Turing machines (classical) and complex numbers (quantum). But the ability of classical math to model all this is truly extraordinary. https://www.dartmouth.edu/~matc/MathDrama/reading/Wigner.htm...

Oh OK. Yeah, I assumed quantum did reals for probabilities. Might not apply if using complex numbers.

Re: Physicists Create World’s First Time Crystal

#115

Post by lisper »

nickpsecurity wrote: post #114
lisper wrote: post #100

Earlier quoted context omitted.

The difference between classical and quantum is not really analogous to the difference between digital and analog, it's the difference between real numbers and Turing machines (classical) and complex numbers (quantum). But the ability of classical math to model all this is truly extraordinary. https://www.dartmouth.edu/~matc/MathDrama/reading/Wigner.htm...

Oh OK. Yeah, I assumed quantum did reals for probabilities. Might not apply if using complex numbers.

Probabilities are always real (by definition). QM uses complex numbers for amplitudes, not probabilities. The probability is the square of the absolute value of the amplitude. Why nature should choose such a weird rule is the Big Mystery. The best discussion of this that I know of is this one:

http://www.scottaaronson.com/democritus/lec9.html

Re: Physicists Create World’s First Time Crystal

#116

Post by ttctciyf »

lisper wrote: post #112
ttctciyf wrote: post #108

Earlier quoted context omitted.

Hi, I'm considerably less of a physicist than yourself :) I did watch your google talk video, and have to thank you for an interesting presentation that introduced me to a couple of new perspectives on quantum interpretation. I'm utterly unqualified to have an opinion on the topic, but enjoy thinking about it sometimes. So I just wanted to ask in respect of "no one has ever pointed out any actual mistakes" - have you…

I have not seen this particular exchange, but it is typical of people who have missed the point. Yes, of course the EPRG paradox doesn't work. That's the whole point . It's a straw man, designed to draw attention to the fact that there is something wrong with QM pedagogy. The thing that people who critique my work generally miss is that it is not about physics, it's about pedagogy . It's about how the physics is expl…

Heh, thanks for the explanation, and sorry for apparently ruining your day :)

I did suspect that "Garret then claims that this can be used for superluminal communication" missed that you were using this as a kind of reductio, but I then took it to mean that your reductio was not working how you expected it to. Probably I should re-watch the video - it's been a couple of years.

Re: Physicists Create World’s First Time Crystal

#117

Post by davesque »

lisper wrote: post #60
davesque wrote: post #51

Earlier quoted context omitted.

Thanks for the great explanation. Serious question: Can I ask how you happen to know so much about this subject?

Years of practice :-) Seriously though, I don't actually know much about QM, I only know the One Thing that makes the rest of QM easy to understand (kind of like knowing Lisp makes the rest of computer programming easy to understand). In case you want to know that One Thing, it's written up here: http://www.flownet.com/ron/QM.pdf There's also a movie version: https://www.youtube.com/watch?v=dEaecUuEqfc

Didn't realize it was you, Dr. Garret. Thanks a lot for taking the time to chat with us about this.

Re: Physicists Create World’s First Time Crystal

#118

Post by lisper »

ttctciyf wrote: post #116
lisper wrote: post #112

Earlier quoted context omitted.

I have not seen this particular exchange, but it is typical of people who have missed the point. Yes, of course the EPRG paradox doesn't work. That's the whole point . It's a straw man, designed to draw attention to the fact that there is something wrong with QM pedagogy. The thing that people who critique my work generally miss is that it is not about physics, it's about pedagogy . It's about how the physics is expl…

Heh, thanks for the explanation, and sorry for apparently ruining your day :) I did suspect that "Garret then claims that this can be used for superluminal communication" missed that you were using this as a kind of reductio, but I then took it to mean that your reductio was not working how you expected it to. Probably I should re-watch the video - it's been a couple of years.

You didn't ruin my day, it actually feels good to vent every now and then. :-)

> your reductio was not working how you expected it to

Actually, it pretty much works exactly how I expected, and has for 25 years (I started down this road in 1990 when the EPRG paradox first occurred to me. It took me ten years to find someone who knew the answer.)

The problem is when people look at EPRG out of context and think that my thesis is that I've invented FTL and therefore I am the World's Greatest Physicist. (And now some moron is probably going to cite this very comment and say that I've claimed to be the Worlds Greatest Physicist because they saw that I wrote "... I am the World's Greatest Physicist" and they don't have time to read the part that they elided.)

Re: Physicists Create World’s First Time Crystal

#119

Post by lisper »

davesque wrote: post #117
lisper wrote: post #60

Earlier quoted context omitted.

Years of practice :-) Seriously though, I don't actually know much about QM, I only know the One Thing that makes the rest of QM easy to understand (kind of like knowing Lisp makes the rest of computer programming easy to understand). In case you want to know that One Thing, it's written up here: http://www.flownet.com/ron/QM.pdf There's also a movie version: https://www.youtube.com/watch?v=dEaecUuEqfc

Didn't realize it was you, Dr. Garret. Thanks a lot for taking the time to chat with us about this.

My pleasure :-)

Re: Physicists Create World’s First Time Crystal

#120

Post by Jcol1 »

lisper wrote: post #115
nickpsecurity wrote: post #114

Earlier quoted context omitted.

Oh OK. Yeah, I assumed quantum did reals for probabilities. Might not apply if using complex numbers.

Probabilities are always real (by definition). QM uses complex numbers for amplitudes , not probabilities. The probability is the square of the absolute value of the amplitude. Why nature should choose such a weird rule is the Big Mystery. The best discussion of this that I know of is this one: http://www.scottaaronson.com/democritus/lec9.html

Can you eli5?
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