Viewpoint: Crystals of Time Researchers propose how to realize time crystals, structures whose lowest-energy states are periodic both in time and space.
http://physics.aps.org/articles/v5/116 quote <<Time crystals may sound dangerously close to a perpetual motion machine, but it is worth emphasizing one key difference: while time crystals would indeed move periodically in an eternal loop, rotation occurs in the ground state, with no work being carried out nor any usable energy being extracted from the system. Finding time crystals would not amount to a violation of well-established principles of thermodynamics. If they can be created, time crystals may have intriguing applications, from precise timekeeping to the simulation of ground states in quantum computing schemes. But they may be much more than advanced devices. Could the postulated cyclic evolution of the Universe be seen as a manifestation of spontaneous symmetry breaking akin to that of a time crystal? If so, who is the observer inducing—by a measurement—the breaking of the symmetry of time?>> end quote Comment: If the time crystal continues to "beat" at the same rate despite being measured then it violates the second law of thermodynamics. Harry
