On the broken time translation symmetry in macroscopic systems: Precessing states and off-diagonal long-range order

  title={On the broken time translation symmetry in macroscopic systems: Precessing states and off-diagonal long-range order},
  author={Grigory E. Volovik},
  journal={JETP Letters},
  • G. Volovik
  • Published 7 September 2013
  • Physics
  • JETP Letters
The broken symmetry state with off-diagonal long-range order (ODLRO), which is characterized by the vacuum expectation value of the operator of creation of the conserved quantum number Q, has the time-dependent order parameter. However, the breaking of the time translation symmetry is observable only if the charge Q is not strictly conserved and may decay. This dichotomy is resolved in systems with quasi-ODLRO. These systems have two well separated relaxation times: the relaxation time τQ of… 

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