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Yale Physicists Find Signs of a Time Crystal (yale.edu)
Yale physicists have uncovered hints of a time crystal, a form of matter that "ticks" when exposed to an electromagnetic pulse, in a child's toy. The discovery means there are now new puzzles to solve, in terms of how time crystals form in the first place. Yale News reports: Ordinary crystals such as salt or quartz are examples of three-dimensional, ordered spatial crystals. Their atoms are arranged in a repeating system, something scientists have known for a century. Time crystals, first identified in 2016, are different. Their atoms spin periodically, first in one direction and then in another, as a pulsating force is used to flip them. That's the "ticking." In addition, the ticking in a time crystal is locked at a particular frequency, even when the pulse flips are imperfect.
Monoammonium phosphate (MAP) crystals are considered so easy to grow that they are sometimes included in crystal growing kits aimed at youngsters. It would be unusual to find a time crystal signature inside a MAP crystal, [Yale Physics professor Sean Barrett] explained, because time crystals were thought to form in crystals with more internal "disorder." The researchers used nuclear magnetic resonance (NMR) to look for a DTC signature -- and quickly found it. Another unexpected thing happened, as well. "We realized that just finding the DTC signature didn't necessarily prove that the system had a quantum memory of how it came to be," said Yale graduate student Robert Blum, a co-author on the studies. "This spurred us to try a time crystal 'echo,' which revealed the hidden coherence, or quantum order, within the system," added Rovny, also a Yale graduate student and lead author of the studies. The findings are described in a pair of studies, one in the journal Physical Review Letters and the other in the journal Physical Review B.
Monoammonium phosphate (MAP) crystals are considered so easy to grow that they are sometimes included in crystal growing kits aimed at youngsters. It would be unusual to find a time crystal signature inside a MAP crystal, [Yale Physics professor Sean Barrett] explained, because time crystals were thought to form in crystals with more internal "disorder." The researchers used nuclear magnetic resonance (NMR) to look for a DTC signature -- and quickly found it. Another unexpected thing happened, as well. "We realized that just finding the DTC signature didn't necessarily prove that the system had a quantum memory of how it came to be," said Yale graduate student Robert Blum, a co-author on the studies. "This spurred us to try a time crystal 'echo,' which revealed the hidden coherence, or quantum order, within the system," added Rovny, also a Yale graduate student and lead author of the studies. The findings are described in a pair of studies, one in the journal Physical Review Letters and the other in the journal Physical Review B.
I think you mean to ask how *precise* it is. The mentioned applications (atomic clocks, laser gyros) are all precision applications.
Many practical applications would depend on being able to manufacture crystals that have a specific desired frequency,. For example quartz timepieces employ a quartz crystal that is machined by lasers or polishing to have a precise resonant frequency of 2^15 (32768) Hz, enabling one watch after another to keep precisely the same time. You just route the oscillator output through 15 frequency dividers and you get a 1 second signal to drive a stepper motor.
But we're talking about is a more exotic process and it's not clear you could tweak time crystals that way.
There's been recent work to develop chip-sized atomic clocks. These are more precise than quartz but could be use on battery-powered circuit boards. This kind of application would requiring mass producing time crystals with the same frequency, even if it wasn't a convenient one like 2^15.
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What the actual goddamned fucking hell is that supposed to mean?!
Some hippy crystal shit right there. Like, the universe remembers, man.
Quantum physics still makes no sense, I could barely find one sentence in that summary I even understood, and it still makes no sense.
Is this shit actually science or is it gibberish like string theory?
The difference between an oscillator and a time crystal, is that an oscillator generally has a resonant spatial structure (usually a spatial crystal or atomic band-gaps) that captures energy (near a resonate frequency or harmonic) and converts it to work near a preferred oscillation frequency. Since the oscillation is actually physical transition with inefficiencies mean that there is a limited 'Q' factor
A time crystal on the other hand is an emergent temporal sub-harmonic structure. Since a time crystal does not require a spatial structure to convert energy into work there is the potentiality for them to have a much better 'Q' factors.
The interesting thing about time crystals is that locally they break time-symmetry like spatial crystals break local spatial symmetry.
Spatial crystals break local spatial symmetry so spatial interactions (translational or rotational) between particles and stable spatial crystals can change momentum of the particles in stable ways because of conservation of momentum (which is basically of how typical electronic oscillators work) being an emergent property of spatial symmetry (Noether's theorem)
Time crystals break local temporal symmetry so temporal interactions between particles and stable time crystals can directly change the energy of the particles in stable ways because of conservation of energy being an emergent property of temporal symmetry.