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arXiv · 2211.06115

Categorical actions of generalised braids for $n=3$

Lorenzo De Biase
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Abstract

Khovanov and Thomas constructed a categorical action of the braid group $Br_n$ on the derived category $D(T^* Fl_n)$ of coherent sheaves on the cotangent bundle of the variety $Fl_n$ of the complete flags in $\mathbb{C}^n$. In this paper, we define the generalised braid category $GBr_3$, give a sufficient condition for the existence of a skein-triangulated $GBr_3$ categorical action, and construct a categorical action of $GBr_3$ on $D(T^*(Fl_3(\bar{i}))$ that generalises Khovanov and Thomas categorical braid action on $D(T^* Fl_3)$.

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Lorenzo De Biase. 2022-11-11. Categorical actions of generalised braids for $n=3$. https://arxiv.org/abs/2211.06115

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