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arXiv · 2212.08625

Bi-$\eta$ and bi-$\lambda$ deformations of $\mathbb{Z}_4$ permutation supercosets

Ben Hoare·Nat Levine·Fiona K. Seibold
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Abstract

Integrable string sigma models on AdS$_3$ backgrounds with 16 supersymmetries have the distinguishing feature that their superisometry group is a direct product. As a result the deformation theory of these models is particularly rich since the two supergroups in the product can be deformed independently. We construct bi-$\eta$ and bi-$\lambda$ deformations of two classes of $\mathbb{Z}_4$ permutation supercoset sigma models, which describe sectors of the Green-Schwarz and pure-spinor string worldsheet theories on type II AdS$_3$ backgrounds with pure R-R flux. We discuss an important limit of these models when one supergroup is undeformed. The associated deformed supergravity background should preserve 8 supersymmetries and is expected to have better properties than the full bi-deformation. As a step towards investigating the quantum properties of these models, we study the two-loop RG flow of the bosonic truncation of the bi-$\lambda$ deformation.

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Ben Hoare, Nat Levine, Fiona K. Seibold. 2022-12-16. Bi-$\eta$ and bi-$\lambda$ deformations of $\mathbb{Z}_4$ permutation supercosets. https://doi.org/10.1007/jhep04(2023)024

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