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Can someone explain what this means? It makes sense that physical laws are symmetrical in space. But in time? I thought that would not be the case because of entropy/irreversible processes etc. What am I missing? The whole article rests on this premise.
>But the laws of physics are not only symmetrical in space but also in time. Can someone explain what this means? It makes sense that physical laws are symmetrical in space. But in time? I thought that would not be the case because of entropy/irreversible processes etc. What am I missing? The whole article rests on this premise.
When you look at each particle in the thermodynamic system, you can easily see there is indeed simmetry in time.
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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
>But the laws of physics are not only symmetrical in space but also in time. Can someone explain what this means? It makes sense that physical laws are symmetrical in space. But in time? I thought that would not be the case because of entropy/irreversible processes etc. What am I missing? The whole article rests on this premise.
https://en.m.wikipedia.org/wiki/Noether%27s_theorem
Groundbreaking stuff. But it is not something you would want to go over in a weekend.
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
Cool, thanks for the info.
...and can someone tell me where the actual time comes into play?
Sure, one can say it is "something not unlike" the manipulation of time, and yet... somehow... it seems like we're just deciding to call it something it is not, since it certainly seems similar enough.
If I carve a piece of wood, such that it resembles a gun, it can play the part of a gun, but only until a person with an actual gun challenges me to a duel.
Can someone explain what computations using __zero energy__ from related article [1] actually means ? [1] https://www.technologyreview.com/s/426917/physicists-predict... """ Another is the possibility that it may be possible to exploit time crystals to perform computations using zero energy. As Wilczek puts it, “it is interesting to speculate that a…quantum mechanical system whose states could be interpreted as a col…
They literally mean "not spending any energy doing the computation". We spend energy on computation for two fundamental reasons: 1) zeroing data and 2) error correction. You avoid zeroing data by doing reversible computation. You avoid error correction by finding really really well behaved / stable systems. Time crystals are reversible basically by definition, and Wilczek is saying that maybe there might be some time…
His work on anyons coupled with his work on time crystals makes him highly qualified to speak on what would be useful computational structures.
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
Earlier quoted context omitted.
IIRC reversible computations only take zero energy if you perform them infinitely slowly.
Just curious, is there a difference between infinitely slowly and not at all?