A tale of two saddles

@article{Chandrasekaran2022ATO,
  title={A tale of two saddles},
  author={Venkat Chandrasekaran and Netta Engelhardt and Sebastian Fischetti and Sergio Hernandez-Cuenca},
  journal={Journal of High Energy Physics},
  year={2022},
  volume={2022}
}
We find a new on-shell replica wormhole in a computation of the generating functional of JT gravity coupled to matter. We show that this saddle has lower action than the disconnected one, and that it is stable under restriction to real Lorentzian sections, but can be unstable otherwise. The behavior of the classical generating functional thus may be strongly dependent on the signature of allowed perturbations. As part of our analysis, we give an LM-style construction for computing the on-shell… 

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