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  • Open Access

Timelike entanglement entropy revisited

Xin Jiang* and Haitang Yang†

  • *Contact author: domoki@stu.scu.edu.cn
  • †Contact author: hyanga@scu.edu.cn
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Phys. Rev. D 113, 106021 – Published 19 May, 2026

DOI: https://doi.org/10.1103/rl9b-373v

Abstract

We present an operator-algebraic definition for timelike entanglement entropy in quantum field theory under a few mild postulates. This rigorously defined timelike entanglement entropy is real-valued due to the timelike tube theorem. We further demonstrate why the timelike entanglement entropy should be real-valued from both path integral argument and holography perspective.

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Phys. Rev. D 113, 106021– Published 19 May, 2026
  • Received 16 December 2025
  • Accepted 8 May 2026
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