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Eternal change for no energy: A time crystal finally made real

#1
C C Offline
https://www.quantamagazine.org/first-tim...-20210730/

INTRO: In a preprint posted online Thursday night, researchers at Google in collaboration with physicists at Stanford, Princeton and other universities say that they have used Google’s quantum computer to demonstrate a genuine “time crystal” for the first time.

A novel phase of matter that physicists have strived to realize for many years, a time crystal is an object whose parts move in a regular, repeating cycle, sustaining this constant change without burning any energy.

“The consequence is amazing: You evade the second law of thermodynamics,” said co-author Roderich Moessner, director of the Max Planck Institute for the Physics of Complex Systems in Dresden, Germany. That’s the law that says disorder always increases.

Time crystals are also the first objects to spontaneously break “time-translation symmetry,” the usual rule that a stable object will remain the same throughout time. A time crystal is both stable and ever-changing, with special moments that come at periodic intervals in time.

The time crystal is a new category of phases of matter, expanding the definition of what a phase is. All other known phases, like water or ice, are in thermal equilibrium: Their constituent atoms have settled into the state with the lowest energy permitted by the ambient temperature, and their properties don’t change with time. The time crystal is the first “out-of-equilibrium” phase: It has order and perfect stability despite being in an excited and evolving state.

“This is just this completely new and exciting space that we’re working in now,” said Vedika Khemani, a condensed matter physicist now at Stanford who co-discovered the novel phase while she was a graduate student and co-authored the new paper.

Khemani, Moessner, Shivaji Sondhi of Princeton and Achilleas Lazarides of Loughborough University in the United Kingdom discovered the possibility of the phase and described its key properties in 2015; a rival group of physicists led by Chetan Nayak of Microsoft Station Q and the University of California, Santa Barbara identified it as a time crystal soon after.

Researchers have raced to create a time crystal over the past five years, but previous demos, though successful on their own terms, have failed to satisfy all the criteria needed to establish the time crystal’s existence. “There are good reasons to think that none of those experiments completely succeeded, and a quantum computer like [Google’s] would be particularly well placed to do much better than those earlier experiments,” said John Chalker, a condensed matter physicist at the University of Oxford who wasn’t involved in the new work.

Google’s quantum computing team made headlines in 2019 when they performed the first-ever computation that ordinary computers weren’t thought to be able to do in a practical amount of time. Yet that task was contrived to show a speedup and was of no inherent interest. The new time crystal demo marks one of the first times a quantum computer has found gainful employment.

“It’s a fantastic use of [Google’s] processor,” Nayak said.

With today’s preprint, which has been submitted for publication, and other recent results, researchers have fulfilled the original hope for quantum computers. In his 1982 paper proposing the devices, the physicist Richard Feynman argued that they could be used to simulate the particles of any imaginable quantum system.

A time crystal exemplifies that vision. It’s a quantum object that nature itself probably never creates, given its complex combination of delicate ingredients. Imaginations conjured the recipe, stirred by nature’s most baffling laws... (MORE)

VIDEO (Fermilab/youtube): Are time crystals real? ... Oct 12, 2018
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#2
Syne Offline
No, the second law of thermodynamics is not violated, nor even "evaded," by an oscillating ground state.

Time crystals do not violate the laws of thermodynamics: energy in the overall system is conserved, such a crystal does not spontaneously convert thermal energy into mechanical work, and it cannot serve as a perpetual store of work. But it may change perpetually in a fixed pattern in time for as long as the system can be maintained. They possess "motion without energy"—their apparent motion does not represent conventional kinetic energy.
- https://en.wikipedia.org/wiki/Time_cryst...modynamics


Just more scientists/science journalists talking out of their ass.
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