• Corpus ID: 209202484

Absence of temporal order in states with spatial correlation decay

  title={Absence of temporal order in states with spatial correlation decay},
  author={Yichen Huang},
  journal={arXiv: Statistical Mechanics},
  • Yichen Huang
  • Published 3 December 2019
  • Physics
  • arXiv: Statistical Mechanics
In quantum lattice systems, we prove that any stationary state with power-law (or even exponential) decay of spatial correlations has vanishing macroscopic temporal order in the thermodynamic limit. Assuming translational invariance, we obtain a similar bound on the temporal order between local operators at late times. Our proofs do not require any locality of the Hamiltonian. Applications in quantum time crystals are briefly discussed. 
Reply to "Comment on "Quantum Time Crystals from Hamiltonians with Long-Range Interactions""
In the note by Khemani et al. [arXiv:2001.11037] the authors express conceptual disagreement with our recent paper on quantum time crystals [Phys. Rev. Lett. 123, 210602]. They criticise the


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