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Scientist Investigate A Brand New Form of Matter: Time Crystals (sciencealert.com)
The discovery of "non-equilibrium matter" could re-write the rules of physics. Long-time Slashdot reader jasonbrown quotes ScienceAlert: For months now, there's been speculation that researchers might have finally created time crystals — strange crystals that have an atomic structure that repeats not just in space, but in time, putting them in perpetual motion without energy. Now it's official — researchers have just reported in detail how to make and measure these bizarre crystals. And two independent teams of scientists claim they've actually created time crystals in the lab based off this blueprint, confirming the existence of an entirely new form of matter.
Both teams -- one at Harvard and the other at the University of Maryland -- have submitted their findings to peer-reviewed publications, according to the article, and "the fact that two separate teams have used the same blueprint to make time crystals out of vastly different systems is promising."
Both teams -- one at Harvard and the other at the University of Maryland -- have submitted their findings to peer-reviewed publications, according to the article, and "the fact that two separate teams have used the same blueprint to make time crystals out of vastly different systems is promising."
Let me guess, all you need is bleach, ammonia, a penny, and blowing bubbles in it with a soda straw to grow these amazing 'time crystals'?
This sounds too much like an April Fool's post!
in their ground state.
However, that would violate quantum electrodynamics, because then you would know the atoms exact momentum and location.
???
The two lasers that were periodically nudging the ytterbium atoms were producing a repetition in the system at twice the period of the nudges, something that couldn't occur in a normal system.
When they're saying 'twice the period of the nudges', do they mean twice the frequency of the nudges, or twice the duration of the nudges? What I'm after here is, is whether or not they're actually implying that there's more energy coming out of this than is being put into it, and by the way unless I'm totally misreading it, it sounds like this isn't 'perpetual motion' at all, not in the sense I think of 'perpetual motion', because they have to 'nudge' it with a pulse from a laser to cause this effect to occur -- unless what I'm missing here, is that all they have to do is 'nudge' it once, and it starts a self-sustaining oscillation? Even if it's self-sustaining once started, isn't it then in a state of equilibrium regardless, and any attempt to tap into the energy of that oscillation would cause it to stop?
... so my watch can use even less energy with the "perpetual moving crystal" as a time base. What, you say it has to be cooled to 0K to actually behave fundamentally different from conventional crystals? Too bad...
Smarter people than you say otherwise:
Thinking for a moment like I'm reading a science fiction novel, what if the energy sustaining it's oscillation is coming from outside the physical Universe, from 'subspace', if you will? Ignoring the possibility, especially in the face of accepted facts like the continual expansion of the Universe, and the 'spooky action at a distance' of entangled particles, is rather foolish, don't you think? To believe that we've discovered all there is to discover in physics is about as arrogant as you can get.
While cool i agree, and i can see perhaps some esoteric use beyond basic research, what sort of practical day-to-day use for the common man would there be?
Quite likely, it's too early to tell.
There is a story, perhaps apocryphal or misattributed, of then-prime-minister Benjamin Disraeli visiting Michael Faraday's lab, and asking Faraday "what use is electricity?" Faraday replied: "What use is a new-born baby?"
If it weren't for deadlines, nothing would be late.
These are just oscillatory systems, of a particular form that have structural integrity as of the dynamics of the system instead of rigidity. Thermodynamics and time going forward are still the same, it's a bit naive to say it's a new form of matter when it's a system of elements.
Perpetual motion machines are allowed by the laws of physics. The galaxy is one for example, it perpetually rotates effectively forever, and by definition beyond what we can measure.
What IS impossible, is to remove energy from the system. If you do that, any machine stops, eventually, unless you add it back in somehow.
excitingthingstodo.blogspot.com
I remember reading about some sci-fi author who wanted a huge interstellar space ship millions of miles long but the control system would take hours to affect a course correction so some physicist postulated a cable made of a material with a 4th dimensional component thus cutting communication time way down.
Anything that moves or vibrates radiates some energy. Hence such crystals would provide "free" energy and that is very, very, very unlikely to be possible in this universe.
It's also very, very, very unlikely that you are not as smart as you think you are.
In any universe.
Smarter people than you say otherwise:
This. Mod parent up.
Quantum-mechanical systems in their ground state cannot radiate energy, because they are already in their lowest possible energy-state.
If it weren't for deadlines, nothing would be late.
( I hope these researchers are certain about their findings ... )
It must have been something you assimilated. . . .
There's a difference between perpetual motion and free perpetual energy.
Someone already did. You're welcome.
A clock more precise than the atomic ones?
What do you think all the crystals are in the Final Fantasy games?
#DeleteFacebook
I got bunch of 16MHz time crystals in my electronic parts box.
Omg the timecube guy was right.....
The one I know, also likely to be apocryphal, is where William Gladstone, then Chancellor of the Exchequer, asked the same question. Faraday's reputed reply was, "Why, sir, there is every probability that you will soon be able to tax it."
Yeah, I heard that one too. Thanks for adding it.
If it weren't for deadlines, nothing would be late.
Anything that moves or vibrates radiates some energy. Hence such crystals would provide "free" energy and that is very, very, very unlikely to be possible in this universe.
Nope, not necessarily. The state of the material is its lowest energy "ground" state. Quantum mechanical ground states can easily have overall dynamical motion, but avoid interaction with the electromagnetic field that would cause radiation because there's no state with lower energy. These will act the same as normal matter - they'll give off energy from breaking bonds when you break them, but are otherwise inert.
You might note the summary states these findings were submitted to "peer-reviewed publications"... not that they were accepted for publication.
Bose-Einstein Condensate has exactly the same property,except the regularity. The overlap of the particle wave means that the system moves inevitably, re-creating the bulk through time on the same organisation as the space bulk organisation.
https://en.wikipedia.org/wiki/...
This sounds interesting to say the least, but I'd be more interested to hear about what potential applications these "time crystals" might be used for.
High-density storage? Super-batteries? Time portals?
Just cruising through this digital world at 33 1/3 rpm...
Asimov clearly covered this ground in his brilliant paper "The Endochronic Properties of Resublimated Thiotimoline".
Nothing to see here. Move on.
Mkay. Based on that logic we could migrate all our garbage and nuclear waste to mexico, it is our basic human right after all.
Dilithium has the same sort of structure.
If you want to cleave a dilithium crystal you have to whack it last month, hit it now, and tap it lightly a week from next tuesday.
Can't find the citation on memory alpha; must have been one of the novels.
"Reality is that which, when you stop believing in it, doesn't go away." - Philip K. Dick
Newton wasn't a lawyer.
rewriting history since 2109
Will this mean fewer of those entertaining police chases that are a staple of our Arizona evening news? Cops see a van riding low on its springs and give chase. When it crashes in the desert after being pursued through city streets, twenty people pile out and run in different direction no, like roaches when you lift a rock.
What if something were so tightly packed that it started absorbing neutrinos and other particles that would normally travel straight through regular matter?
Helium-4 seems to do something strange when cooled to a super-liquid - it's just not possible to cool down into a solid because the kinetic energy exceeds the electron bond strengths.
https://phys.org/news/2009-05-...
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I wonder, would an asteroid (or even the Earth itself) qualify as a time crystal? They also move continually in a pattern, without expending energy to do so.
I don't care if it's 90,000 hectares. That lake was not my doing.
Look, pop-science journalists usually don't understand what they're reporting on, so the frequently garble it. They also insert unwarranted hype. This doesn't say ANYTHING about the report they base their story on. (If you want details, look at their source.)
I think we've pushed this "anyone can grow up to be president" thing too far.
It violates the second law. But so does a superconductor, so who cares.
what sort of practical day-to-day use for the common man would there be?
What practical use does the common man have for anything he can't eat, drink or fuck?
When all you have is a hammer, every problem starts to look like a thumb.
An object that moves even in a ground state must expend energy.
Did you just confuse velocity with acceleration?
When all you have is a hammer, every problem starts to look like a thumb.
I wonder, would an asteroid (or even the Earth itself) qualify as a time crystal?
No, because it is not a crystal. My counter-wonder: what happened to the quality of Slashdot commentary?
When all you have is a hammer, every problem starts to look like a thumb.
No, because it is not a crystal.
Ah, I guess you missed the part of the article where it described a time-crystal as a structure that repeats its pattern over time, instead of (or in addition to) across space. Hence the name, "time crystal".
My counter-wonder: what happened to the quality of Slashdot commentary?
It all went downhill after people decided that gratuitous insults were more worthwhile than engaging in polite discussion of the topic at hand. This was especially embarrassing in cases where it turned out their alleged "gotcha" was in fact a product of their own lack of understanding of the subject.
I don't care if it's 90,000 hectares. That lake was not my doing.
This reads like a passage from a Hunter S. Thompson essay.
The world's burning. Moped Jesus spotted on I50. Details at 11.
The two lasers that were periodically nudging the ytterbium atoms were producing a repetition in the system at twice the period of the nudges, something that couldn't occur in a normal system.
When they're saying 'twice the period of the nudges', do they mean twice the frequency of the nudges, or twice the duration of the nudges?
I read it as twice the period. Continuing with the rest of the section you quoted:
"Wouldn't it be super weird if you jiggled the Jell-O and found that somehow it responded at a different period?" said Yao.
Not at all:
- If the jello jiggles at 2 Hz and you tap it every half-second, It's not hard at all to get it to dance indefinitely at four times the rate, one quarter the period, of the periodic stimulus. Ditto a high-Q resonator - like a bell. Hit it at the corresponding phase every Nth cycle, often enough that it doesn't
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
...
"Wouldn't it be super weird if you jiggled the Jell-O and found that somehow it responded at a different period?" said Yao.
Not at all:
- If the jello jiggles at 2 Hz and you tap it every half-second, It's not hard at all to get it to dance indefinitely at four times the rate, one quarter the period, of the periodic stimulus. Ditto a high-Q resonator - like a bell. Hit it at the corresponding phase every Nth cycle, often enough that it doesn't decay appreciably, and the bell will appear to ring merrily at N times the frequency of the stimulus, forever.
- Getting something to react periodically at HALF, or 1/Nth, the rate of the stimulus, is a bit more difficult but still not hard. With Jello, for instance, you'd have to hit it in a way that would encourage it to continue in it's way in either half-cycle. Imagine a Jello tower leaning right and left, and tapping its base upward to encourage it to lean more just as it passes the middle going in either direction. That would keep it pumped up.
There are lots of ways to get that latter to work, even without a period tuned to a natural frequency of the thing being provoked:
- A flip-flop divide by two counter. Clock once, changes state. Clock again, changes back to the other state.
- A platform with a slinky in the bottom of one end of an upside-down U-shaped tube. Thump the platform up, and the slinky loops into the other leg of the U. Mechanical flip-flop.
- A wooden platform with, say, a surface feature consisting of a ring of five similar segments shaped so that, if you put a bead in the low spot of one segment, a thump makes it jump to and settle into the next segment around the loop. Put one (or some combination of up to five identical or distinguished - like by color - beads, into the low spots and the pattern of beads moves around among different configurations, returning to starting point every fifth stimulus.
I could go on for hours.
The point is that it may not be immediately obvious, but there's nothing "new physics" about a system stimulated at one rate and going through a set of state transitions that repeats periodicly, to achieve a "wiggle" of an integer fraction of the stimulus.
= = = =
And I suspect that is what is happening here. As I read it, a real time crystal would oscillate without any external stimulus.
It looks to me that, in trying to create their "time crystal", they oversimplified by making a small part of a much larger (perhaps infinite) candidate and using the lasers to simulate the boundary conditions from its connection with the rest of the candidate structure. In doing so they risk creating, instead, something like the divide-by-N situations I described above, with the boundary condition simulator providing the clock for the counter.
Call me when they get one to run without any lasers (or other external pump), say by bending their "conga line" into a circle or folding it into a polygon.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Pics or it won't happen.
sub f{($f)=@_;print"$f(q{$f});";}f(q{sub f{($f)=@_;print"$f(q{$f});";}f});
Attempting to read the article made me feel dumb.
So I read the comments, and now feel like a genius.
And there the problem starts. It is fascinating to see how much deeply stupid people are around here that do not even understand how limited their understanding is. The current models for Quantum Mechanics are not truth. They are rough approximations and, if history is any indicator, quite a few things presented by the press as "truth" in there will turn out to have exceptions and inaccuracies. The other problem is that actual observation is now down to indirections of indirections and only mathematical models try to explain what is actually happening there. These models could easily be way off with the lack of quality in th experimental validation.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
The Earth radiates energy through gravity waves, which means that its orbit is slowly decaying. The operative word here is "slowly": the power is about 200 watts, or roughly the power output of a mediocre Tour de France rider over a four hour stage. At that rate the Sun will go nova well before there is any measurable difference in orbit.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
No. It's scientists* investigate.
There are two teams. This is not one scientist. How does the OP not know the difference between singular and plural?
- Zav - Imagine a Beowulf cluster of insensitive clods...
And I'm not sure "object" and "motion" exactly apply here.
There are three types of perpetual motion machines, each of which is impossible for different reasons. A perpetual motion machine of the first type is impossible because it violates conservation of energy. A perpetual motion machine of the second type is impossible because it violates the second law of thermodynamics (e.g. by extracting thermal energy from a reservoir without having a cooler reservoir to dump waste heat). A perpetual motion of the third type is impossible because you can't build a machine that doesn't have friction.
Notice how the third type is impossible for a different kind of reason. A system which is perpetually changing in a periodic manner doesn't necessarily violate any physical laws, unless the motion characterizes something you can characterize as a bearing.
The crux of people's objections here is that a "time crystal" sounds a lot like a perpetual motion machine of the third type. But it's not a "machine" of any kind: it's a crystal structure. And motion on that kind of physical scale is a squirrelly concept. Is the electronic resonance of a benzene ring "motion", and an election an "object"? If so then a benzene molecule is a perpetual motion machine.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
So is a rotating fan a time crystal?
Some drink at the fountain of knowledge. Others just gargle.
Glass IS a slow moving liquid. Wait long enough and your window melted.
I can't imagine time crystals but can I buy a bag of them to go? What could a man do with 20 lbs. of time crystals?
The version I read, in a biography of Benjamin Franklin, is that he was observing one of the first balloon flights of the Montgolfier Brothers in France, and another observer asked what good was it, and Franklin replied, "What good is a new born baby."
In theory, theory and practice are the same; in practice they're different. (Yogi Berra & A. Einstein)
It's up for debate:
http://news.emory.edu/stories/...
https://www.sciencedaily.com/r...
http://www.nature.com/news/wor...
Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
Can I cast fireballs with them? Or mix potions? Or will they capture the soul on critical strike, so it could be used to enchant my sword?
No country just let's you walk in uninvited.
Mm hm.
You kids these days, spoiled rotten and woefully uneducated.
LOL. Suggestion: Learn how to use apostrophes before you accuse others of being uneducated.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
Anything that moves? Everything moves. Everything, ever, moves.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
The current models for quantum mechanics are not rough approximations. They're astonishingly exact models. If history is any indicator, what we'll see is what we expect. Quantum mechanics is very frustrating that way: without some success at getting results that don't follow the model, there's no good way to improve the model.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
and no reference to Blinx.
You know, I really liked that game.
In numbers, yes. In values of "true", they are rough approximations. It is the latter we are talking about here.
Incidentally, classical mechanics is also an "astonishing exact model" with regards to accuracy in many circumstances. It just happens to be very far from complete and there are conditions where its accuracy becomes bad enough that the model breaks down completely and becomes "untrue".
The same is very likely the case for quantum mechanics, yet all these science-fanatics (that are universally bad scientists or no scientists) think that quantum mechanics represents absolute truth. It does not. On the level of understand what is actually going on, it is a rough approximation. The difference is that we know what circumstances classical mechanics needs to be a good model, yet we do not know them for quantum mechanics and that makes the approximation "rough".
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
I think he was more taking exception to your use of the word "rough"
Which.. I have to kind of say I do, too.
I fully understand what you're saying regarding the tough-to-swallow-pill that we live in a universe ruled by statistics with seemingly random constants punched in.
But there's nothing "rough" about the approximation QM and QED provide us.
It's upsettingly exact and for all the people like you (and I) who don't like the taste of a universe governed in such a way, upsettingly infallible.
It is our theory of how everything we can interact with works- and it's 100% correct in every instance we have the energy to test.
I use "rough" intentionally, because that is what I mean. If there were only minor deviations and the theory would essentially be correct in all situations, I would not use "rough". However, as in the example with classical mechanics, it is quite possible that there are situations were the model basically fails completely, and that is why I call it a "rough" approximation.
Incidentally, no, we do not have 100% correctness. We have pretty good correctness in the sense that results are within the margins of error from what the theory predicts in the cases tried and where the experimental results are observed trough a number of indirections. For classical mechanics, high accuracy in all observed situations was true for a long, long time as well. Then new experiments were done with new technology, because some small deviations crept up in some experiments that eventually could not be explained away with observational errors anymore. The experiments done to confirm Quantum Theory are pretty limited in comparison to the situations that are physically possible and there are some experiments underway that have not yet had conclusive results, for example the experiment whether computations on larger number of entangled particles actually behave according to theory (i.e. whether quantum computing actually works when you have a few hundred entangled particles or more). Sure, these experiments are hugely difficult and complicated, but the same is true for the experiments needed to show the limitations of classical mechanics when you take the state-of-the-art of technology back then into account.
I am not saying the science is bad. I am just saying there are good reasons to believe the currently known models are incomplete and should not be taken as absolute. We may eventually have a GUT (Grand Unifying Theory) and then really have a "true" and complete model of physics. But at this time we are not there and it is unclear whether we will ever get there.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
*except superconductors
I use "rough" intentionally, because that is what I mean. If there were only minor deviations and the theory would essentially be correct in all situations, I would not use "rough". However, as in the example with classical mechanics, it is quite possible that there are situations were the model basically fails completely, and that is why I call it a "rough" approximation.
And I still object whole-heartedly with that logic. You're claiming it's rough because it has not been disproven. That's a piss-poor argument.
Incidentally, no, we do not have 100% correctness.
Incidentally, I'm unaware of any non-pedantic argument you could make to back up that claim.
As I said, we have correctness within the energy levels we can test with. Sure the margins of error are there, but they're impressively standing up well to the march of technology. I'd love to be schooled otherwise here, because all I see from you is fallacious logic.
Quantum mechanics is very impressive. But an inner voice tells me that it is not yet the real thing. The theory produces a good deal but hardly brings us closer to the secret of the Old One. I am at all events convinced that He does not play dice.
An inner voice tells me that guy isn't wrong. And that you and I agree on that point. But I think you're doing QM and QED a wild injustice by calling it a rough approximation with a lack of proof to back it up. At least Einstein was honest that he had nothing but a feeling.
Many comments, many minds, many ideas. I wonder, what would be the most coherent?