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arXiv · alg-geom/9503007

Quotient Spaces Modulo Algebraic Groups

János Kollár
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Abstract

The paper proves that if a reductive group scheme acts properly on a scheme then the geometric quotient exists as an algebraic space. As a consequence we obtain the existence of the moduli spcace of canonically polarized varieties over Spec Z.

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János Kollár. 1995-03-16. Quotient Spaces Modulo Algebraic Groups. https://arxiv.org/abs/alg-geom/9503007

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