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arXiv · 2207.07389

Motivic invariants of birational maps

Hsueh-Yung Lin·Evgeny Shinder
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Abstract

We construct invariants of birational maps with values in the Kontsevich--Tschinkel group and in the truncated Grothendieck groups of varieties. These invariants are morphisms of groupoids and are well-suited to investigating the structure of the Grothendieck ring and L-equivalence. Building on known constructions of L-equivalence, we prove new unexpected results about Cremona groups.

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Hsueh-Yung Lin, Evgeny Shinder. 2022-07-15. Motivic invariants of birational maps. https://arxiv.org/abs/2207.07389

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