• Corpus ID: 242757218

Reductive quotients of klt singularities

@inproceedings{Braun2021ReductiveQO,
  title={Reductive quotients of klt singularities},
  author={Lukas Braun and Daniel Greb and Kevin Langlois and Joaqu'in Moraga},
  year={2021}
}
We prove that the quotient of a klt type singularity by a reductive group is of klt type. In particular, given a klt variety X endowed with the action of a reductive group G and admitting a quasiprojective good quotient X Ñ X{{G, we can find a boundary B on X{{G so that the pair pX{{G,Bq is klt. This applies for example to GIT-quotients of klt varieties. Our main result has consequences for complex spaces obtained as quotients of Hamiltonian Kähler G-manifolds, for collapsings of homogeneous… 

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