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Spectral functions at nonzero temperature

V. P. Nair1 and Robert D. Pisarski2

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Phys. Rev. D 113, 074022 – Published 16 April, 2026

DOI: https://doi.org/10.1103/m4st-sddq

Abstract

We present a straightforward derivation of the spectral representation of a scalar field at nonzero temperature, assuming that the field is relativistically invariant in vacuum. This form was first derived by Bros and Buchholz.

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References (21)

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Phys. Rev. D 113, 074022– Published 16 April, 2026
  • Received 16 April 2025
  • Accepted 9 February 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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