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  • Open Access

Composite AdS geodesics for CFT correlators and timelike entanglement entropy

Hardik Bohra1,* and Allic Sivaramakrishnan2,†

  • *Contact author: bohra.hardik@uky.edu
  • †Contact author: allic@caltech.edu
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Phys. Rev. D 114, 026015 – Published 10 July, 2026

DOI: https://doi.org/10.1103/4crg-9y1b

Abstract

We study how to recover timelike worldlines in AdS from CFT data as a toy model for holographically reconstructing realistic observers. We give a bulk extremization procedure that determines composite timelike-spacelike geodesics that connect timelike-separated boundary points. The total geodesic length matches the length extracted from CFT correlators at the timelike-separated points. We show agreement in Poincaré AdS, for generic boundary points in global AdS, and also for the Bañados-Teitelboim-Zanelli solution, in which the timelike segment probes behind the horizon. We refine related methods to compute timelike entanglement entropy in AdS3/CFT2 and recover known results.

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Phys. Rev. D 114, 026015– Published 10 July, 2026
  • Received 16 February 2026
  • Accepted 23 June 2026
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