T-duality across non-extremal horizons

Maxime Medevielle; Thomas Mohaupt

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arXiv · 2401.00296

T-duality across non-extremal horizons

Maxime Medevielle·Thomas Mohaupt

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Abstract

When applying T-duality to a generic, non-extreme Killing horizon, T-duality is spacelike on one side and timelike on the other. We show, using simple examples from four-dimensional Einstein-Maxwell theory, that the image of the horizon is a singularity which can be understood as an interface between two different T-dual theories and their solutions. Using an embedding into type-II string theory, we show that the singularity occurs when scalars reach the boundary of moduli space, resulting in a breakdown of the effective field theory due to the presence of tensionless strings.

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Maxime Medevielle, Thomas Mohaupt. 2023-12-30. T-duality across non-extremal horizons. https://arxiv.org/abs/2401.00296

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