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    The all-loop non-Abelian thirring model and its RG flow
    Itsios, Georgios; Sfetsos, Konstadinos; Siampos, Konstadinos; Ίτσιος, Γεώργιος; Σφέτσος, Κωνσταντίνος; Σιάμπος, Κωνσταντίνος
    We analyze the renormalization group flow in a recently constructed class of integrable sigma-models which interpolate between WZW current algebra models and the non-Abelian T-duals of PCM for a simple group G. They are characterized by the integer level k of the current algebra, a deformation parameter lambda and they exhibit a remarkable invariance involving the inversion of lambda. We compute the beta-function for lambda to leading order in 1/k. Based on agreement with previous results for the exact beta-function of the non-Abelian bosonized Thirring model and matching global symmetries, we state that our integrable models are the resummed version (capturing all counterterms in perturbation theory) of the non-Abelian bosonized Thirring model for a simple group G. Finally, we present an analogous treatment in a simple example of a closely related class of models interpolating between gauged WZW coset CFTs and the non-Abelian T-duals of PCM for the coset G/H.
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    The classical Yang–Baxter equation and the associated Yangian symmetry of gauged WZW-type theories
    Itsios, Georgios; Sfetsos, Konstantinos; Siampos, Konstantinos; Torrielli, Alessandro; Ίτσιος, Γεώργιος; Σφέτσος, Κωνσταντίνος; Σιάμπος, Κωνσταντίνος
    We construct the Lax-pair, the classical monodromy matrix and the corresponding solution of the Yang–Baxter equation, for a two-parameter deformation of the Principal chiral model for a simple group. This deformation includes as a one-parameter subset, a class of integrable gauged WZW-type theories interpolating between the WZW model and the non-Abelian T-dual of the principal chiral model. We derive in full detail the Yangian algebra using two independent methods: by computing the algebra of the non-local charges and alternatively through an expansion of the Maillet brackets for the monodromy matrix. As a byproduct, we also provide a detailed general proof of the Serre relations for the Yangian symmetry.
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    Compactifications of the Klebanov-Witten CFT and new AdS3 backgrounds
    Bea, Yago; Edelstein, Jose; Itsios, Georgios; Kooner, Karta; Nunez, Carlos; Schofield, Daniel; Sierra-Garcia, J. Anibal; Ίτσιος, Γεώργιος
    In this paper we find various new backgrounds in Type IIB, IIA and M-theory with an AdS 3-factor. The solutions are smooth and preserve small amounts of SUSY. These new backgrounds are found by application of non-Abelian T-duality (sometimes combined with T-duality) on the supergravity solution dual to the Klebanov-Witten CFT compactified to two dimensions. The field theory aspects encoded by these backgrounds are studied. We give a detailed account of conserved charges, central charges, entanglement entropy and Wilson loops. Further, we present a possible field theory interpretation for our backgrounds.