Mathematics > Algebraic Geometry
arXiv:2604.00511 (math)
[Submitted on 1 Apr 2026 (v1), last revised 24 Jun 2026 (this version, v2)]
Abstract:We generalize the classical semiregularity theorem of Buchweitz and Flenner to the setting of noncommutative algebraic geometry, with group actions. This applies in particular to twisted derived categories, in which case it answers a question of Markman and streamlines part of his proof of the Hodge conjecture for abelian fourfolds. Along the way, we prove that for many finite group actions on derived categories of varieties, the invariant category is of geometric origin.
Submission history
From: Alexander Perry [view email]
[v1]
Wed, 1 Apr 2026 05:53:04 UTC (32 KB)
[v2]
Wed, 24 Jun 2026 15:52:58 UTC (32 KB)
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