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arXiv · 2303.10751

Effective morphisms and quotient stacks

Andrea Di Lorenzo·Giovanni Inchiostro
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Abstract

We give a valuative criterion for when a smooth algebraic stack with a separated good moduli space is the quotient of a separated Deligne-Mumford stack by a torus. For doing so, we introduce a new class of morphisms, the so-called effective morphisms, which are a generalization of separated morphisms.

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Andrea Di Lorenzo, Giovanni Inchiostro. 2023-03-19. Effective morphisms and quotient stacks. https://arxiv.org/abs/2303.10751

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