Description of quantum coherence in thermodynamic processes requires constraints beyond free energy

  title={Description of quantum coherence in thermodynamic processes requires constraints beyond free energy},
  author={Matteo Lostaglio and David Jennings and Terry Rudolph},
  journal={Nature Communications},
Recent studies have developed fundamental limitations on nanoscale thermodynamics, in terms of a set of independent free energy relations. Here we show that free energy relations cannot properly describe quantum coherence in thermodynamic processes. By casting time-asymmetry as a quantifiable, fundamental resource of a quantum state, we arrive at an additional, independent set of thermodynamic constraints that naturally extend the existing ones. These asymmetry relations reveal that the… 
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