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arXiv · 2203.15645

Equivalent birational embedding IV: reduced varieties

Massimiliano Mella
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Abstract

Two reduced projective schemes are said to be Cremona equivalent if there is a Cremona map that maps one in the other. In this paper I revise some of the known results about Cremona equivalence and extend the main result of [MP09] to reduced schemes. This allows to prove a very general contractibility result for union of rational subvarieties.

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Massimiliano Mella. 2022-03-29. Equivalent birational embedding IV: reduced varieties. https://arxiv.org/abs/2203.15645

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