Work

Integrability of the λ-deformation of the PCM with spectators

Year: 2025

Type: article

Abstract: A bstract We construct a generalisation of the λ -deformation of the Principal Chiral Model (PCM) where we deform just a subgroup F of the full symmetry group G . We find that demanding Lax integrability imposes a crucial restriction, namely that the coset F\G must be symmetric. Surprisingly, we also find that (when F is non-abelian) integrability requires that the term in the action involving only the spectator fields should have a specific λ -dependence, which is a curious modification of the procedure expected from the known F = G case. The resulting Lax connection has a novel analytical structure, with four single poles as opposed to the two poles of the cases of the PCM and of the standard λ -deformation. We also explicitly work out the example of G = SU(2) and F = U(1), discussing its renormalisation group flow to two loops.

Source: Journal of High Energy Physics

DOI: 10.1007/jhep03(2025)112

Authors: Riccardo Borsato, Georgios Itsios, J. Luis Miramontes, Konstantinos Siampos

Institutions: Universidade de Santiago de Compostela, Humboldt-Universität zu Berlin, Aristotle University of Thessaloniki

Language: English

Topic: Black Holes and Theoretical Physics

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: diamond