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arXiv · 2011.02539

Spin Matrix Theory String Backgrounds and Penrose Limits of AdS/CFT

Troels Harmark·Jelle Hartong·Niels A. Obers·Gerben Oling
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Abstract

Spin Matrix theory (SMT) limits provide a way to capture the dynamics of the AdS/CFT correspondence near BPS bounds. On the string theory side, these limits result in non-relativistic sigma models that can be interpreted as novel non-relativistic strings. This SMT string theory couples to non-relativistic $U(1)$-Galilean background geometries. In this paper, we explore the relation between pp-wave backgrounds obtained from Penrose limits of AdS${}_5 \times S^5$, and a new type of $U(1)$-Galilean backgrounds that we call flat-fluxed (FF) backgrounds. These FF backgrounds are the simplest possible SMT string backgrounds and correspond to free magnons from the spin chain perspective. We provide a catalogue of the $U(1)$-Galilean backgrounds one obtains from SMT limits of string theory on AdS${}_5 \times S^5$ and subsequently study large charge limits of these geometries from which the FF backgrounds emerge. We show that these limits are analogous to Penrose limits of AdS${}_5 \times S^5$ and demonstrate that the large charge/Penrose limits commute with the SMT limits. Finally, we point out that $U(1)$-Galilean backgrounds prescribe a symplectic manifold for the transverse SMT string embedding fields. This is illustrated with a Hamiltonian derivation for the SMT limit of a particle.

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Troels Harmark, Jelle Hartong, Niels A. Obers, Gerben Oling. 2020-11-04. Spin Matrix Theory String Backgrounds and Penrose Limits of AdS/CFT. https://doi.org/10.1007/jhep03(2021)129

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