Courant-Hilbert deformations of Yang-Baxter sigma models

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.

💡 Research Summary

In this work the authors construct a new class of integrable deformations that simultaneously incorporate Yang‑Baxter (YB) deformations and Courant‑Hilbert (CH) deformations within the unified framework of four‑dimensional Chern‑Simons (4D CS) theory. The starting point is the 4D CS action
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