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Thermal quenching of classical and semiclassical scrambling

Vijay Ganesh Sadhasivam1,*, Andrew C. Hunt1, Lars Meuser1,2, Yair Litman1, and Stuart C. Althorpe1,†

  • *Contact author: vgs23@cam.ac.uk
  • †Contact author: sca10@cam.ac.uk
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Phys. Rev. E 110, L012204 – Published 26 July, 2024

DOI: https://doi.org/10.1103/PhysRevE.110.L012204

Abstract

Quantum scrambling often gives rise to short-time exponential growth in out-of-time-ordered correlators. The scrambling rate over an isolated saddle point at finite temperature is shown here to be reduced by a hierarchy of quenching processes. Two of these appear in the classical limit, where escape from the neighborhood of the saddle reduces the rate by a factor of two, and thermal fluctuations around the saddle reduce it further; a third process can be explained semiclassically as arising from quantum thermal fluctuations around the saddle, which are also responsible for imposing the Maldacena-Shenker-Stanford bound.

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Outline

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Phys. Rev. E 110, L012204– Published 26 July, 2024
  • Received 25 March 2024
  • Revised 7 June 2024
  • Accepted 15 July 2024
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