# Deformations of the Almheiri-Polchinski model

## TL;DR

This paper explores deformations of the Almheiri-Polchinski model using Yang-Baxter techniques, resulting in modified black hole solutions with altered spacetime structures and entropy, challenging holographic interpretations.

## Contribution

It introduces a novel deformation of the AP model via Yang-Baxter methods, leading to new solutions with hyperbolic dilaton potentials and modified black hole properties.

## Key findings

- Deformed AdS$_2$ metric solutions obtained.
- Black hole solutions with altered entropy.
- Significant changes in boundary spacetime structure.

## Abstract

We study deformations of the Almheiri-Polchinski (AP) model by employing the Yang-Baxter deformation technique. The general deformed AdS$_2$ metric becomes a solution of a deformed AP model. In particular, the dilaton potential is deformed from a simple quadratic form to a hyperbolic function-type potential similarly to integrable deformations. A specific solution is a deformed black hole solution. Because the deformation makes the spacetime structure around the boundary change drastically and a new naked singularity appears, the holographic interpretation is far from trivial. The Hawking temperature is the same as the undeformed case but the Bekenstein-Hawking entropy is modified due to the deformation. This entropy can also be reproduced by evaluating the renormalized stress tensor with an appropriate counter term on the regularized screen close to the singularity.