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Physicists Create World’s First Time Crystal

technologyreview.com

21–30 of 130 posts

Re: Physicists Create World’s First Time Crystal

#21
post #19

Earlier quoted context omitted.

Does that mean it is continuously changing in a repetitive fashion?

Can any old oscillator be called a time crystal?

No - oscillators need constant energy input in order to operate. Time crystals require no energy for temporal repetition.

Re: Physicists Create World’s First Time Crystal

#22
post #4

What are time crystals? Try this: Physicists Predict The Existence of Time Crystals https://www.technologyreview.com/s/426917/physicists-predict...

This is also helpful: How to Build A Space-Time Crystal https://www.technologyreview.com/s/428334/how-to-build-a-spa...

Re: Physicists Create World’s First Time Crystal

#24
post #17

Earlier quoted context omitted.

Does that mean it is continuously changing in a repetitive fashion?

apparently yes, but because it's in a low energy state, it's impossible to extract any energy from it and do work (otherwise it would be a perpetual motion machine.)

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..)

Re: Physicists Create World’s First Time Crystal

#25
post #20
post #17

Earlier quoted context omitted.

apparently yes, but because it's in a low energy state, it's impossible to extract any energy from it and do work (otherwise it would be a perpetual motion machine.)

It's interesting it is a perpetual motion machine, but it works only as long as you don't use it.

The universe has a perverse sense of humor.

Re: Physicists Create World’s First Time Crystal

#27
post #13

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…

https://en.wikipedia.org/wiki/Zero-point_energy

Re: Physicists Create World’s First Time Crystal

#28
post #21
post #19

Earlier quoted context omitted.

Can any old oscillator be called a time crystal?

No - oscillators need constant energy input in order to operate. Time crystals require no energy for temporal repetition.

That's not really right. You can oscillate without constant energy input. Two particles can orbit forever.

But normally that oscillation represents stored energy.

They key to a time crystal is that it's oscillating while it's in a minimum energy state. It would take energy to make it stop moving.

Re: Physicists Create World’s First Time Crystal

#29
post #6

Ugh, that title though... WTH is a time crystal, and who decided to call it that? I'm not clicking the bait to find out.

The core idea is not too strange, actually. A "normal" crystal has a repeating structure in space; a time crystal is a construct with a repeating temporal structure.

So ... like a regular wave?

Re: Physicists Create World’s First Time Crystal

#30
post #21
post #19

Earlier quoted context omitted.

Can any old oscillator be called a time crystal?

No - oscillators need constant energy input in order to operate. Time crystals require no energy for temporal repetition.

Don't quantum harmonic oscillators oscillate even in their ground state? How is a time crystal different from a garden-variety QHO?
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