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arXiv · 2512.06091

Supergravity realisations of $\lambda$-models

Giuseppe Casale·Georgios Itsios
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Abstract

We construct solutions of type-II supergravity based on multiple copies and/or mixings of $\lambda$-deformed coset CFTs on $\mathrm{SO}(n+1)_k/\mathrm{SO}(n)_k$, with $n = 2, 3, 4$. The resulting ten-dimensional geometries contain undeformed $\mathrm{AdS}$ factors, thereby allowing a connection between $\lambda$-deformations and the AdS/CFT correspondence. Imposing reality conditions on the solutions further constrains the deformation parameter. In some cases these bounds exclude the undeformed ($\lambda = 0$) or non-Abelian T-dual ($\lambda \to 1$) limits. This work extends the results of 1911.12371 and 2411.11086.

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Giuseppe Casale, Georgios Itsios. 2025-12-05. Supergravity realisations of $\lambda$-models. https://arxiv.org/abs/2512.06091

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