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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

#101

Post by lisper »

zer0gravity wrote: post #98
lisper wrote: post #79

Earlier quoted context omitted.

That is (almost) exactly right. The only difference is that with classical states it is possible to distinguish between the object (the light bulb) and the state (on or off). With quantum systems the object is the state, so there is no way to distinguish between "the same atom" and "different atoms with the same state".

So by saying this, you're actually saying that we're living in some sort of state machine / cellular automata universe, and in order to understand it, we just have to find the rules of interaction/propagation of the states ?

No, we are living in a quantum universe (or a quantum multiverse if you prefer). We don't yet know whether space and time are discrete, because we have not yet unified QM and relativity. If space and time turn out to be discrete then yes, the multiverse would be essentially a cellular automaton. But if they aren't then it (probably) isn't.

Re: Physicists Create World’s First Time Crystal

#102

Post by lisper »

jasonwatkinspdx wrote: post #97
lisper wrote: post #92

Earlier quoted context omitted.

You obviously didn't watch even the first minute of the talk because the very first thing I say is that the title is tongue-in-cheek and there is no conspiracy.

I did, though it's been several years. Making an inflammatory statement, then denying it as a joke is a common mild double bind, one that's best avoided. I'm not speaking toward your intentions as I obviously don't know them. I'm just pointing out that particular rhetorical form isn't doing you any favors, again, IMO.

I prefer to think of it as a marketing strategy. And I think it has actually been fairly effective. That video has had over a million views.

Re: Physicists Create World’s First Time Crystal

#103

Post by RangerScience »

lisper wrote: post #77
jasonwatkinspdx wrote: post #69

Earlier quoted context omitted.

Just be aware that while Dr. Garret is very smart (and very accomplished with software) he is not a physicist. When this talk first came out I asked a couple people who do know QFT in detail about it and they were quite dismissive.

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…

As a semi-random person with little connection to you or your critic, I just want you to know their comment just reminded me to critically think about what you're saying, not to think it was wrong or misleading.

Re: Physicists Create World’s First Time Crystal

#104

Post by zer0gravity »

lisper wrote: post #101
zer0gravity wrote: post #98

Earlier quoted context omitted.

So by saying this, you're actually saying that we're living in some sort of state machine / cellular automata universe, and in order to understand it, we just have to find the rules of interaction/propagation of the states ?

No, we are living in a quantum universe (or a quantum multiverse if you prefer). We don't yet know whether space and time are discrete, because we have not yet unified QM and relativity. If space and time turn out to be discrete then yes, the multiverse would be essentially a cellular automaton. But if they aren't then it (probably) isn't.

But "quantum universe" doesn't actually mean that we're working with quanta(s), which translates to infinitesimally small but discrete quantities ?

Aren't Planck constants all about that ?

Re: Physicists Create World’s First Time Crystal

#105

Post by speeder »

zer0gravity wrote: post #104
lisper wrote: post #101

Earlier quoted context omitted.

No, we are living in a quantum universe (or a quantum multiverse if you prefer). We don't yet know whether space and time are discrete, because we have not yet unified QM and relativity. If space and time turn out to be discrete then yes, the multiverse would be essentially a cellular automaton. But if they aren't then it (probably) isn't.

But "quantum universe" doesn't actually mean that we're working with quanta(s), which translates to infinitesimally small but discrete quantities ? Aren't Planck constants all about that ?

He is referring to spacetime actually. quanta we are sure are the smallest objects in space.

Spacetime is a sort of cartesian representation of space and time, with probably 4 axes (x, y, z, time).

Many relativity concepts obey this, for example stuff moving in space at the speed of light, move literally zero on the time axis. And you can calculate the relationship between time and speed by rotating vectors.

So back to quanta: we don't know if time is discrete. We don't even know if time actually exists, or its properties, because the math right now has results that are quite weird (like implying moving backwards in time should be normal and common as moving forward...), also there are arguments over the shape of "spacetime" with most people assuming it is a 4d cube, but maybe it ins't.

Re: Physicists Create World’s First Time Crystal

#108

Post by ttctciyf »

lisper wrote: post #77
jasonwatkinspdx wrote: post #69

Earlier quoted context omitted.

Just be aware that while Dr. Garret is very smart (and very accomplished with software) he is not a physicist. When this talk first came out I asked a couple people who do know QFT in detail about it and they were quite dismissive.

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 seen the stackexchange discussion at http://physics.stackexchange.com/questions/208609/does-the-f... , and do you have any comment on the assertion there that your statement of EPRG misses the point that "even if Alice does let her system produce interference, the other system will not produce interference either"?

Re: Physicists Create World’s First Time Crystal

#109

Post by ivoras »

semiel wrote: post #54
dysfunctor wrote: post #44

Earlier quoted context omitted.

So what are the implications of an object that breaks that symmetry? Would it be possible to observe an object in different times in the same state, or the same time in different states?

> So what are the implications of an object that breaks that symmetry? Would it be possible to observe an object in different times in the same state, or the same time in different states? The object would be in a repeating set of states. First state 1, then state 2, then state 1, then back to state 2, etc. This is not in itself surprising. Think of a pendulum, for instance. The difference here is that the motion is…

But... don't the process by which this is observed (I mean literally, the machinery used to measure it) introduce energy into (or draw it out) this system?

Re: Physicists Create World’s First Time Crystal

#110

Post by omginternets »

lisper wrote: post #45
davesque wrote: post #38

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…

Where does the "time" part come in?
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