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arXiv · 2302.02085

Semicontinuous maps on module varieties

Christof Geiß·Daniel Labardini-Fragoso·Jan Schröer
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Abstract

We study semicontinuous maps on varieties of modules over finite-dimensional algebras. We prove that truncated Euler maps are upper or lower semicontinuous. This implies that $g$-vectors and $E$-invariants of modules are upper semicontinuous. We also discuss inequalities of generic values of some upper semicontinuous maps.

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Christof Geiß, Daniel Labardini-Fragoso, Jan Schröer. 2023-02-04. Semicontinuous maps on module varieties. https://arxiv.org/abs/2302.02085

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