• Corpus ID: 240070894

Unipotent morphisms

@inproceedings{Bragg2021UnipotentM,
  title={Unipotent morphisms},
  author={Daniel Bragg and Jack Hall and Siddharth Mathur},
  year={2021}
}
We introduce the theory of unipotent morphisms of algebraic stacks. We give two applications: (1) a unipotent analogue of Gabber’s Theorem for torsion Gm-gerbes and (2) smooth Deligne–Mumford stacks with quasi-projective coarse spaces satisfy the resolution property in positive characteristic. Our main tool is a descent result for flags, which we prove using results of Schäppi. 
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