Time crystals might exist after all (Update)

September 9, 2016 by Lisa Zyga feature
Credit: CC0 Public Domain

(Phys.org)—Are time crystals just a mathematical curiosity, or could they actually physically exist? Physicists have been debating this question since 2012, when Nobel laureate Frank Wilczek first proposed the idea of time crystals. He argued that these hypothetical objects can exhibit periodic motion, such as moving in a circular orbit, in their state of lowest energy, or their "ground state." Theoretically, objects in their ground states don't have enough energy to move at all.

In the years since, other physicists have proposed various arguments for why the physical existence of is impossible—and most physicists do seem to think that time crystals are physically impossible because of their odd properties. Even though time crystals couldn't be used to generate useful energy (since disturbing them makes them stop moving), and don't violate the second law of thermodynamics, they do violate a fundamental of the laws of physics.

However, now in a new paper published in Physical Review Letters, physicists from the University of California, Santa Barbara (UCSB) and Microsoft Station Q (a Microsoft research lab located on the UCSB campus) have demonstrated that it may be possible for time crystals to physically exist.

The physicists have focused on the implication of time crystals that seems most surprising, which is that time crystals are predicted to spontaneously break a fundamental symmetry called "time-translation symmetry." To understand what this means, the researchers explain what spontaneous symmetry breaking is.

"The crucial difference here is between explicit symmetry breaking and spontaneous symmetry breaking," coauthor Dominic Else, a physicist at UCSB, told Phys.org. "If a symmetry is broken explicitly, then the laws of nature do not have the symmetry anymore; spontaneous symmetry breaking means that the laws of nature have a symmetry, but nature chooses a state that doesn't."

If time crystals really do spontaneously break time-translation symmetry, then the laws of nature that govern time crystals wouldn't change with time, but the time crystals themselves would change over time due to their ground-state motion, spontaneously breaking the symmetry.

Although spontaneously broken time-translation symmetry has never been observed before, almost every other type of spontaneous symmetry breaking has been. One very common example of a spontaneously broken symmetry occurs in magnets. The laws of nature do not impose which side of a magnet will be the north pole and which will be the south pole. The distinguishing feature of any magnetic material, however, is that it spontaneously breaks this symmetry and chooses one side to be the north pole. Another example is ordinary crystals. Although the laws of nature are invariant under rotating or shifting (translating) space, crystals spontaneously break these spatial symmetries because they look different when viewed from different angles and when shifted a little bit in space.

In their new study, the physicists specifically define what it would take to spontaneously break time-translation symmetry, and then use simulations to predict that this broken symmetry should occur in a large class of quantum systems called "Floquet-many-body-localized driven systems." The scientists explain that the key aspect of these systems is that they remain far from thermal equilibrium at all times, so the system never heats up.

The new definition of broken time-translation symmetry is similar to the definitions of other broken symmetries. Basically, when the size of a system (such as a crystal) grows, the time taken for a symmetry-breaking state to decay into a symmetry-respecting state increases, and in an infinite system the symmetry-respecting state can never be reached. As a result, symmetry for the entire system is broken.

"The significance of our work is two-fold: on one hand, it demonstrates that time-translation symmetry is not immune to being spontaneously broken," said coauthor Bela Bauer, a researcher at Microsoft Station Q. "On the other hand, it deepens our understanding that non-equilibrium systems can host many interesting states of matter that cannot exist in equilibrium systems."

According to the physicists, it should be possible to perform an experiment to observe time-translation by using a large system of trapped atoms, trapped ions, or superconducting qubits to fabricate a time crystal, and then measure how these systems evolve over time. The scientists predict that the systems will exhibit the periodic, oscillating motion that is characteristic of time crystals and indicative of spontaneously broken time-translation symmetry.

"In collaboration with experimental research groups, we are exploring the possibility of realizing Floquet time crystals in systems of cold atomic gases," said coauthor Chetan Nayak at Microsoft Station Q and UCSB.

Update: A team of physicists at the Joint Quantum Institute at the University of Maryland have now experimentally confirmed the existence of time crystals for the first time. The team observed the time-crystal behavior predicted in a system of trapped ions. A pre-print is available at: arXiv:1609.08684 [quant-ph]

Explore further: Physicists propose new definition of time crystals—then prove such things don't exist

More information: Dominic V. Else, Bela Bauer, and Chetan Nayak. "Floquet Time Crystals." Physical Review Letters. DOI: 10.1103/PhysRevLett.117.090402 Also at arXiv:1603.08001 [cond-mat.dis-nn]

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bcode
4.6 / 5 (9) Sep 09, 2016
Hrmm... This article has helped to understand that Time Crystals can potentially exist without breaking the laws of physics, but I'm still no closer to understanding what they actually are. It would have been great if the article started with a paragraph about what they are and why we're talking about them.
tinitus
Sep 09, 2016
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tinitus
Sep 09, 2016
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Azrael
3.4 / 5 (10) Sep 09, 2016
@bcode

My very layman and possibly incorrect understanding of a time crystal is a group of particles that exhibit -perpetual- periodic motion (i.e. rotate in a circle, or otherwise return to their starting point over time) in their lowest energy state (ground state) so that, if you were to take snapshots of the system over time and overlay them in some way, the positions of the particles would form something that looks like a crystal structure.

It's basically a perpetual motion machine (usually impossible), but avoids violating laws of physics by being incapable of performing any actual work (You can't extract energy from it... the particles are in their lowest possible energy state).

I have no idea why people would want to make one, other than to say "Hey, that's neat."
Azrael
3.4 / 5 (10) Sep 09, 2016
@bcode

Here's a link to a Popular Science article that has a graphical representation:
http://www.popsci...-crystal
tinitus
Sep 09, 2016
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tinitus
Sep 09, 2016
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tinitus
Sep 09, 2016
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TheGhostofOtto1923
3.3 / 5 (7) Sep 09, 2016
Hrmm... This article has helped to understand that Time Crystals can potentially exist without breaking the laws of physics, but I'm still no closer to understanding what they actually are. It would have been great if the article started with a paragraph about what they are and why we're talking about them
This is the internet.

Do a search and find more comprehensive explanations than can be fit into a physorg press release.
https://www.google.com/

My very layman and possibly incorrect understanding of a time crystal
-because if you dont research yourself you get a lot of other mental paraplegics who will guess for you and then yet another thread is clogged with tripe.
Sonhouse
not rated yet Sep 09, 2016
How is this different from some kind of matter, say hydroden, at absoute zero but the electrons are still constrained to move around the nucleus no matter what the temperature of the assembly as a whole.
tinitus
Sep 09, 2016
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tinitus
Sep 09, 2016
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tblakely1357
5 / 5 (3) Sep 09, 2016
Hrmm... This article has helped to understand that Time Crystals can potentially exist without breaking the laws of physics, but I'm still no closer to understanding what they actually are. It would have been great if the article started with a paragraph about what they are and why we're talking about them
This is the internet.

Do a search and find more comprehensive explanations than can be fit into a physorg press release.
https://www.google.com/

My very layman and possibly incorrect understanding of a time crystal
-because if you dont research yourself you get a lot of other mental paraplegics who will guess for you and then yet another thread is clogged with tripe.


Ah, the joys of internet douchery.
KBK
1.8 / 5 (10) Sep 09, 2016
There are no laws in physics, only theories exist.

There is also no such thing as a fact.

The ONLY fact that exists, is that there are none. Paradox ---like physics itself.

Every time you see or hear of someone talking about facts and laws in physics, tell them they are buying into religious dogma.

No physicist or intelligent person worth more than a wet fart would ever talk about laws, as laws are about punishing people for violating social conventions and norms.

A law of physics is like a papal bull or fatwa issued from a religious figurehead and biblical tombs system.

Physics has only theories, all of it is theory and if it wasn't --science would be a dead thing, unchanging.

This is the line in the sand - how you separate the real innovators, thinkers and creators from the linear negative proofers.

I've spoken with profs and department heads at the local world class university, and none of them teach such drivel as laws.

So where does this crap come from?
KBK
1.7 / 5 (6) Sep 09, 2016
also, symmetry does not exist as time is considered unidirectional.

Time...which, by being what it is observed as being...explicitly states that symmetry in physics cannot and does not exist.

When we can travel both forward and backward in time, then we can maybe force a bubble of symmetry to exist.

Until then... this three dimensional unidirectional time based universe of so-called atoms and particles -----will remain wholly asymmetrical.
Eikka
1 / 5 (1) Sep 09, 2016
The concept of time crystal is just another denomination of the question: "can we observe, how something makes neverending periodic motion at the quantum level"?


The concept of a time crystal implies a thing that has structure over time the same as over space. To observe one moving is to observe an object that moves through time at a different rate than you.

A time crystal is an oxymoron, because it would imply an object that exists right here, right now, that still moves in its zero energy state where all movement by definition has stopped. The trouble is that in order to observe something moving, you must be able to measure its momentum, and to do that you must extract energy out of the object, and where there is no energy no momentum can be measured.
Eikka
3.7 / 5 (3) Sep 09, 2016
No physicist or intelligent person worth more than a wet fart would ever talk about laws, as laws are about punishing people for violating social conventions and norms.


You've fallen into the valley of postmodernism.

Walk on.
Azrael
3.3 / 5 (7) Sep 09, 2016

My very layman and possibly incorrect understanding of a time crystal
-because if you dont research yourself you get a lot of other mental paraplegics who will guess for you and then yet another thread is clogged with tripe.


What is the point of this ad-hominem, Otto? Do you feel better about yourself now?
tinitus
Sep 09, 2016
This comment has been removed by a moderator.
Azrael
3.3 / 5 (7) Sep 09, 2016
How is this different from some kind of matter, say hydroden, at absoute zero but the electrons are still constrained to move around the nucleus no matter what the temperature of the assembly as a whole.


The position of an electron around the nucleus is probabilistic. They don't really orbit the nucleus like a planet orbits a star. That being said, they wouldn't periodically move about a point in an orderly way to fit the definition of a space-time crystal.
Azrael
3.3 / 5 (7) Sep 09, 2016
The concept of a time crystal implies a thing that has structure over time the same as over space
Nope, the concept of space-time crystal is https://en.wikipe..._crystal and it's testable.


Just FYI. The Wikipedia article you link to says very nearly the same thing in the first sentence that Eikka said, to which you replied "Nope".
tinitus
Sep 09, 2016
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baudrunner
not rated yet Sep 09, 2016
The problem with this theorizing is that at ground state all the atoms in a system behave as a single atom. In other words, no localization is taking place so such particles cannot co-exist with the rest of reality, only in a closed system.
Semmster
1 / 5 (1) Sep 09, 2016
Oh, Oh, Oh, it's Magic!
TheGhostofOtto1923
3 / 5 (6) Sep 09, 2016
What is the point of this ad-hominem, Otto? Do you feel better about yourself now?
A little, thanks for asking. What's the point of criticizing a good site like this because it doesn't spoon feed you the minimum you need to know about a subject in order to understand the article?

And what's the point of offering opinions which are prefaced by 'I don't know what I'm talking about but...'?

And what's the point of reminding lazy people that if they really want to know about something they can fucking Google it and find good reliable sources of comprehensive info?

These are some questions which come to mind.
Eikka
1 / 5 (1) Sep 09, 2016
It's really just about periodic motion.


If so, then the idea of a time crystal is an oxymoron as I already explained.

With no measurable, in other words extractable energy in the ground state, no motion can exist in a meaningful way because motion implies energy. Even if you said the "crystal" is moving in some sense with no energy, the rest of reality could not tell the difference, therefore the motion is not real and does not exist as far as anyone or anything else is concerned.

seattle
not rated yet Sep 09, 2016
Aren't these some examples of time crystals?

-A wall clock
-Sun-Earth revolutions
-Schrodinger quantum states (time-varying) / Zitterbewegung
Azrael
3 / 5 (6) Sep 09, 2016
And what's the point of offering opinions which are prefaced by 'I don't know what I'm talking about but...'?


I didn't offer an opinion. I offered a possibly incomplete or erroneous recollection of what I remembered from an article that was written months ago, and prefaced it with "Layman and possibly incorrect" because I might have omitted or misunderstood a detail in the description I gave him, and wanted to highlight the fact that I'm not an expert in the field.

I then found an article with a better description, and a graphical representation, and provided a link for him.

Your "mental paraplegics" comment was completely uncalled for.

These are some questions which come to mind.


Here's a question that comes to mind: What's the point of you being a jerk to random people on the internet?

Sorry about your low self esteem.

Macksb
1 / 5 (1) Sep 09, 2016
I have made many comments in Physorg about periodic oscillators, their tendency to coordinate or couple their oscillations in groups small and large, and the particular patterns in which they self-organize their oscillations and their own relative positions.

My "coupled periodic oscillator" comments on Physorg go back to 2010, which predates this time crystal idea (2012).

So I take a great interest in Wilczek's "time crystals." As the article says, "these hypothetical objects can exhibit periodic motion, such as moving in a circular orbit, in their state of lowest energy, or 'ground state." "The scientists predict that the systems will exhibit ...periodic, oscillating motion." Periods, orbits, cycles, oscillations--these are my areas of interest, which I have applied by way of comments to more than 100 Physorg articles.

I'm rooting for them and their time crystals.
Jayded
3 / 5 (2) Sep 10, 2016
@KBK - Dont speak such drivel. All theories are comprised of laws which are required in order to sustain the theory. Thus when someone speaks of the law of something they do not imply that it is bonded in factual, physical reality. They instead refer to an object (law) or series of objects (laws) which together are the sum expression of a theory and if violated immediately invalidate a theory. If the term scares you so much you can supplant "laws" with any term that makes you feel safe at night.
tinitus
Sep 10, 2016
This comment has been removed by a moderator.
TheGhostofOtto1923
2.3 / 5 (9) Sep 10, 2016
I didn't offer an opinion. I offered a possibly incomplete or erroneous recollection of what I remembered from an article that was written months ago
Right. You guessed rather than doing something useful like finding a link or posting an excerpt. People like me who have been here awhile and who take the time to research and post facts get a little frustrated when people waste time and thread space. And especially when they criticize the site for being something it's not.

The main advantage of the internet is instant access to valid facts. We don't have to guess any more and we don't have to tolerate people who do.
Here's a question that comes to mind: What's the point of you being a jerk to random people on the internet?
And what's the point of sharing your thoughts on the internet if you can't stand a little snark?

I'm sure you'll grow some stones or find something less disturbing to do.
JimD
1 / 5 (2) Sep 10, 2016
I wonder what interaction a physical time crystal would have with the universe. If it violates time-translation symmetry then would it periodically "wink" into and out of existence?
adam_russell_9615
3 / 5 (2) Sep 10, 2016
"Theoretically, objects in their ground states don't have enough energy to move at all. "

My understanding from laser theory is that atoms in their ground state do have energy.
Am I misunderstanding laser theory or are you talking about a different "ground state"?
tinitus
Sep 10, 2016
This comment has been removed by a moderator.
Hyperfuzzy
5 / 5 (1) Sep 10, 2016
How?
Eikka
3 / 5 (2) Sep 10, 2016
Objects in ground quantum state just cannot transfer energy to another objects. They can still move, but this movement cannot be mediated to another objects.


If no energy transfer can happen, then you can't observe that the object is in motion. Movement or no movement must make some difference, and since measuring an object at zero energy gives you back zero energy whether it moves or not, you can't tell the difference - in other words, the motion isn't real.
Osiris1
5 / 5 (1) Sep 11, 2016
Will a time crystal emanate temporal radiation?
Azrael
3.4 / 5 (5) Sep 11, 2016
You guessed rather than doing something useful like finding a link or posting an excerpt


Recalling what I remembered isn't "guessing", but then again, you already know that. You're just intentionally misconstruing what happened. It's a smokescreen.

In other news that won't shock anyone: A bully, when called out for being a bully, first downplays his bullying (A little snark), and then tries to justify his bullying (we don't have to tolerate people who do).

You could lead a much happier life if you got help for your problems, instead of lashing out at people to feel better about yourself.
tinitus
Sep 11, 2016
This comment has been removed by a moderator.
Phys1
5 / 5 (4) Sep 11, 2016
Objects in the ground state can absorb energy and thus the properties of the ground state can be observed.
Eikka
5 / 5 (1) Sep 11, 2016
If no energy transfer can happen, then you can't observe that the object is in motion
It implies, that at the zero temperature all objects should disappear.


Yes, and that is exactly why the absolute zero can never actually be reached.

Objects in the ground state can absorb energy and thus the properties of the ground state can be observed.


The issue here is that motion implies momentum, which implies energy. To observe that something has momentum, you must transfer energy out of it. Of course the object can absorb energy and gain momentum, but that's just you making it move, not observing that it was moving.

Motion without momentum is non-real, like a shadow moving across a wall - the shadow is not an object that moves - it's merely an illusion of motion.
tinitus
Sep 11, 2016
This comment has been removed by a moderator.
tinitus
Sep 11, 2016
This comment has been removed by a moderator.
AmritSorli
1 / 5 (2) Sep 11, 2016
Time cristals are pure illusion. Time has only the mathematical existence. http://www.scienc...d=122019
RNP
4 / 5 (4) Sep 11, 2016
@AmritSorli
Oh PLEASE! Another snake oil salesman pedaling his wares.
EnsignFlandry
not rated yet Sep 12, 2016
Objects at 0 K still have energy, the random energy of quantum movement. Classical thermodynamics eventually transitions to quantum thermodynamics.

And I made $20 today holding up a sign by the road.
antialias_physorg
3.7 / 5 (3) Sep 12, 2016
I wonder what interaction a physical time crystal would have with the universe. If it violates time-translation symmetry then would it periodically "wink" into and out of existence?

Time crystals are simply a form a of matter that if you take a snapshot at
1) t = 0 you will find it in (ordered) state X
2) at time t=t1 you will find it in ordered state Y
3) at t=2*t1 you will find it in ordered state X
4) at t = 3t1 you will find it in ordered state Y
etc., etc.
(that is for a cyrstal with tow ordered phases. The usual representation has a circular motion with an infinity of ordered phases but which repeat periodically.)
The difference between this and simply taking an ordinary crystal and spinning it around is: The oscillation/periodic motion happens even at the lowest energy state without any additional energy input from the outside.

There's no mystical temporal winking-in-and-out-back-and-forth-in-time component.
Hyperfuzzy
1 / 5 (2) Sep 12, 2016
I'm an EE, i put some time crystals in my morning cereal and wrote this next week, the 18th. I wonder if it will show up on the 12th.
antialias_physorg
5 / 5 (1) Sep 13, 2016
I'm an EE,

A lie if ever I saw one. (Alternatively you're really a shame to the EE profession)
Guy_Underbridge
not rated yet Sep 13, 2016
i put some time crystals in my morning cereal and wrote this next week, the 18th. I wonder if it will show up on the 12th
I'd ask you next Sunday, but I don't think you'll be there...
JimD
1 / 5 (1) Sep 13, 2016
I wonder what interaction a physical time crystal would have with the universe. If it violates time-translation symmetry then would it periodically "wink" into and out of existence?

Time crystals are simply a form a of matter that if you take a snapshot at
1) t = 0 you will find it in (ordered) state X
2) at time t=t1 you will find it in ordered state Y
3) at t=2*t1 you will find it in ordered state X
4) at t = 3t1 you will find it in ordered state Y
etc., etc.
(that is for a cyrstal with tow ordered phases. The usual representation has a circular motion with an infinity of ordered phases but which repeat periodically.)
The difference between this and simply taking an ordinary crystal and spinning it around is: The oscillation/periodic motion happens even at the lowest energy state without any additional energy input from the outside.

There's no mystical temporal winking-in-and-out-back-and-forth-in-time component.


"Mystical?" You're an idiot.
antialias_physorg
5 / 5 (2) Sep 13, 2016
There's no mystical temporal winking-in-and-out-back-and-forth-in-time component.

"Mystical?" You're an idiot.

Well, you're the one that came up with the 'wink in and out of existence' BS
(i.e. you didn't even bother to look up what a time crystal is before posting)

So about the 'idiot' thing: Right back at'cha.
Hyperfuzzy
not rated yet Sep 13, 2016
I'm an EE, i put some time crystals in my morning cereal and wrote this next week, the 18th. I wonder if it will show up on the 12th.

Wow, and I haven't even written this yet!
Steelwolf
not rated yet Oct 09, 2016
I wonder if DNA could be considered a system of interacting time crystals and the animals or plants that form from them are just their temporal expression, the propagation of each system dependent upon each other in sequence yet showing an overall temporally moving wave form with differing amplitudes due to differing life types, speed of propagation and intelligence level along with how much they affect the surrounding space/matter.

This may actually be their undiscovered base for Dark Mater and Dark Energy, is from within such crystalline time structures and their reiterations.

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