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arXiv · 1510.03083

Yang-Baxter sigma models and Lax pairs arising from $κ$-Poincaré $r$-matrices

Andrzej Borowiec·Hideki Kyono·Jerzy Lukierski·Jun-ichi Sakamoto·Kentaroh Yoshida
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Abstract

We study Yang-Baxter sigma models with deformed 4D Minkowski spacetimes arising from classical $r$-matrices associated with $κ$-deformations of the Poincaré algebra. These classical $κ$-Poincaré $r$-matrices describe three kinds of deformations: 1) the standard deformation, 2) the tachyonic deformation, and 3) the light-cone deformation. For each deformation, the metric and two-form $B$-field are computed from the associated $r$-matrix. The first two deformations, related to the modified classical Yang-Baxter equation, lead to T-duals of dS$_4$ and AdS$_4$\,, respectively. The third deformation, associated with the homogeneous classical Yang-Baxter equation, leads to a time-dependent pp-wave background. Finally, we construct a Lax pair for the generalized $κ$-Poincaré $r$-matrix that unifies the three kinds of deformations mentioned above as special cases.

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Andrzej Borowiec, Hideki Kyono, Jerzy Lukierski, Jun-ichi Sakamoto, Kentaroh Yoshida. 2016-04-20. Yang-Baxter sigma models and Lax pairs arising from $κ$-Poincaré $r$-matrices. https://doi.org/10.1007/jhep04(2016)079

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