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arXiv · 2602.04662

Courant-Hilbert deformations of Yang-Baxter sigma models

Osamu Fukushima·Takaki Matsumoto·Kentaroh Yoshida
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Abstract

We present integrable deformations of Yang-Baxter (YB) sigma models based on the Courant-Hilbert (CH) construction. To this end, we employ the four-dimensional Chern-Simons theory, in which the CH construction is shown in arXiv:2509.22080. As a result, the CH construction works in an intricate way alongside the YB deformations. Remarkably, the resulting deformed action can also be expressed as the sum of the master formula Lagrangian and the trace of the energy-momentum tensor. This result indicates the universality of the correction term.

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Osamu Fukushima, Takaki Matsumoto, Kentaroh Yoshida. 2026-02-04. Courant-Hilbert deformations of Yang-Baxter sigma models. https://arxiv.org/abs/2602.04662

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