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arXiv · 2408.15752

Geometric Interpretation of Timelike Entanglement Entropy

Michal P. Heller·Fabio Ori·Alexandre Serantes
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Abstract

Analytic continuations of holographic entanglement entropy in which the boundary subregion extends along a timelike direction have brought a promise of a novel, time-centric probe of the emergence of spacetime. We propose that the bulk carriers of this holographic timelike entanglement entropy are boundary-anchored extremal surfaces probing analytic continuation of holographic spacetimes into complex coordinates. This proposal not only provides a geometric interpretation of all the known cases obtained by direct analytic continuation of closed-form expressions of holographic entanglement entropy of a strip subregion but crucially also opens a window to study holographic timelike entanglement entropy in full generality. We initialize the investigation of complex extremal surfaces anchored on a timelike strip at the boundary of anti-de Sitter black branes. We find multiple complex extremal surfaces and discuss possible principles singling out the physical contribution.

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Michal P. Heller, Fabio Ori, Alexandre Serantes. 2025-03-31. Geometric Interpretation of Timelike Entanglement Entropy. https://doi.org/10.1103/physrevlett.134.131601

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