2025/07/28 by Ovidiu Racorean, Racorean, Ovidiu · 2 voices · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Relativity and Gravitational Theory
paper · doi:10.1016/j.physletb.2025.139767
openalex publication_date 2025/07/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We derive the metric of the BTZ black hole for the special case of interchanging the characteristics of space and time coordinates. We maximally extend the geometry of this interior solution and show that the line element is similar to its exterior solution counterpart. Thus, we assign the thermofield double state dual to this interior geometric construction. As a result, we have two independent thermofield double states corresponding to the BTZ metric: one dual to the exterior solution and one dual to the interior solution. In this scenario, considering both thermofield double states as dual to the full BTZ black hole, we evaluate the partition function of the bulk. The partition function represents a non-orientable spacetime. Additionally, we derive a thermofield double-like state that connects in the gravity dual the regions of spacetime with opposite orientations of space and time. We conclude by discussing the connections between the partition function of the full BTZ black hole and topological invariants that characterize many-body topological phases of matter protected by orientation-reversing symmetries.