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arXiv · 2101.12515

Twisted motivic Chern class and stable envelopes

Jakub Koncki·Andrzej Weber
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Abstract

We present a definition of {\em twisted motivic Chern classes} for singular pairs $(X,\Delta)$ consisting of a singular space $X$ and a $\mathbb Q$-Cartier divisor containing the singularities of $X$. The definition is a mixture of the construction of motivic Chern classes previously defined by Brasselet-Sch{\"u}rmann-Yokura with the construction of multiplier ideals. The twisted motivic Chern classes are the limits of the elliptic classes defined by Borisov-Libgober. We show that with a suitable choice of the divisor $\Delta$ the twisted motivic Chern classes satisfy the axioms of the stable envelopes in the K-theory. Our construction is an extension of the results proven by the first author for the fundamental slope.

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Jakub Koncki, Andrzej Weber. 2021-01-29. Twisted motivic Chern class and stable envelopes. https://arxiv.org/abs/2101.12515

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