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arXiv · 2512.07967

Trim resolutions, stringy and Mather classes, and IC characteristic cycles

Paolo Aluffi
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Abstract

We introduce trim resolutions of complex algebraic varieties, a strengthening of the notion of small resolution. We prove that the characteristic cycle of the intersection cohomology sheaf of a variety admitting a trim resolution is irreducible and that for such varieties the stringy and Chern-Mather classes coincide.

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Paolo Aluffi. 2025-12-08. Trim resolutions, stringy and Mather classes, and IC characteristic cycles. https://arxiv.org/abs/2512.07967

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