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Could this be used for very stable time measurements, as an alternative to atomic clocks?
"One reason why space-time crystals are interesting is that their periodicity in time makes them natural clocks. So there should be plenty of people with more than a passing interesting in making one."
So I took from that, yes, this could be an alternative to atomic clocks.
I figured this article would fly over my head (which it mostly did), but it was actually a very fun read. My main takeaway was the paradox that the interesting arrangement of matter could be in its lowest energy state, yet still moving. And that no energy could be extracted from this movement. I'm probably butchering the concept with my misuse of terminology but whatevs.
I don't know anything about anything, but I want to enumerate some things I learned reading this article, and if someone actually knows what they're talking about and sees fit to take pity on me, please correct me so that I can understand what this actually means. So a time crystal appears to be made up of real matter. The article mentions ions that are arranged in a certain particular way, cooled in order to reduce…
>They did this, and observed the ions changing in such a way where there was no driving influence and it's implied that the reason that this behavior was observed is because time symmetry was broken, which is just a fancy way of alleging that the universe is non-deterministic, I think. Time translational symmetry and determinism have nothing to do with one another. Even a classical pendulum breaks time translational…
I figured this article would fly over my head (which it mostly did), but it was actually a very fun read. My main takeaway was the paradox that the interesting arrangement of matter could be in its lowest energy state, yet still moving. And that no energy could be extracted from this movement. I'm probably butchering the concept with my misuse of terminology but whatevs.
- matter / energy is neither added nor removed to retain shape/movement
- the energy/matter within the "crystal" change state/position in a repeating and/or predictable matter
- pattern retains even when the energy is at extreme lows
This would be analogous to a water cycle. The water changes state in a predictable manner, water heats up (due to the sun) and evaporates. As the molecules get closer to space, the cool and attract each other to form clouds. The clouds hit a maximum and rain occurs flowing back into bodies of water again.
The difference is that the water cycle needs the presence of heat/cooling from external sources while the time crystal can exist at "zero degree" temperatures.
Earlier quoted context omitted.
This is also helpful: How to Build A Space-Time Crystal https://www.technologyreview.com/s/428334/how-to-build-a-spa...
Thanks for both those links. That article is from 2012 and quotes: "If that’s the case, we ought to be reading the details about the first space-time crystal sometime in the days and weeks to come. " Was there something non obvious they had to overcome that took the extra few years to produce these space-time crystals? (I use the term non obvious as if this was not all way beyond my ken!)
In any event, they sure seem to have made a lot of progress in just a few years. I look forward to reading more about this, as well as listening to Neil deGrasse Tyson describe it in his infectiously enthusiastic way.
I figured this article would fly over my head (which it mostly did), but it was actually a very fun read. My main takeaway was the paradox that the interesting arrangement of matter could be in its lowest energy state, yet still moving. And that no energy could be extracted from this movement. I'm probably butchering the concept with my misuse of terminology but whatevs.
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…
Also, when you say there are not discrete things, do you mean in the QFT sense of field excitations?
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/Reversible_computing?wprov=sfl...