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arXiv · 2408.14567

Strings in AdS$_3$: one-loop partition function and near-extremal BTZ thermodynamics

Christian Ferko·Sameer Murthy·Mukund Rangamani
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Abstract

We revisit the computation of the string partition function in AdS$_3$ focussing on the appearance of spacetime (super) symmetries. We show how the asymptotic symmetries of the AdS$_3$ spacetime, which generate the boundary (super) Virasoro currents, are captured by the one-loop partition sum. We use this to argue that the recent understanding of near-extremal black hole thermodynamics based on the gravitational path integral continues to hold for finite string length. Along the way we clarify some aspects of the AdS$_3$/CFT$_2$ duality and, in particular, deduce which bulk gauge fields lead to boundary currents. We also explain how one can interpolate between supersymmetric and thermal (Atick-Witten) fermion boundary conditions in the target space by suitably tuning rotational chemical potentials in the string partition function.

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Christian Ferko, Sameer Murthy, Mukund Rangamani. 2024-08-26. Strings in AdS$_3$: one-loop partition function and near-extremal BTZ thermodynamics. https://arxiv.org/abs/2408.14567

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