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arXiv · 2107.00023

On the Non-Relativistic Expansion of Closed Bosonic Strings

Jelle Hartong·Emil Have
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Abstract

We develop a novel approach to non-relativistic closed bosonic string theory that is based on a string $1/c^2$ expansion of the relativistic string, where $c$ is the speed of light. This approach has the benefit that one does not need to take a limit of a string in a near-critical Kalb-Ramond background. The $1/c^2$-expanded Polyakov action at next-to-leading order reproduces the known action of non-relativistic string theory provided that the target space obeys an appropriate foliation constraint. We compute the spectrum in a flat target space, with one circle direction that is wound by the string, up to next-to-leading order and show that it reproduces the spectrum of the Gomis-Ooguri string.

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Jelle Hartong, Emil Have. 2021-06-30. On the Non-Relativistic Expansion of Closed Bosonic Strings. https://doi.org/10.1103/physrevlett.128.021602

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