Journal of High Energy Physics

, 2019:18 | Cite as

Spectral representation of thermal OTO correlators

  • Soumyadeep ChaudhuriEmail author
  • Chandramouli Chowdhury
  • R. Loganayagam
Open Access
Regular Article - Theoretical Physics


We study the spectral representation of finite temperature, out of time ordered (OTO) correlators on the multi-time-fold generalised Schwinger-Keldysh contour. We write the contour-ordered correlators as a sum over time-order permutations acting on a fundamental array of Wightman correlators. We decompose this Wightman array in a basis of column vectors, which provide a natural generalisation of the familiar retarded-advanced basis in the finite temperature Schwinger-Keldysh formalism. The coefficients of this decomposition take the form of generalised spectral functions, which are Fourier transforms of nested and double commutators. Our construction extends a variety of classical results on spectral functions in the SK formalism at finite temperature to the OTO case.


Thermal Field Theory Quantum Dissipative Systems Nonperturbative Effects 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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Copyright information

© The Author(s) 2019

Authors and Affiliations

  • Soumyadeep Chaudhuri
    • 1
    Email author
  • Chandramouli Chowdhury
    • 1
    • 2
  • R. Loganayagam
    • 1
  1. 1.International Centre for Theoretical Sciences (ICTS-TIFR)Tata Institute of Fundamental ResearchBangaloreIndia
  2. 2.Department of PhysicsIndian Institute of Technology GuwahatiGuwahatiIndia

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