Algebraic cobordism via spans

Yuki Kato

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arXiv · 2203.05331

Algebraic cobordism via spans

Yuki Kato

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Abstract

We define the algebraic cobordism of $\infty$-categories equipped with universal line bundle data as an initial oriented functor in the associated span category. In the standard motivic framework, this recovers the Thom spectrum model established by Voevodsky, Gepner, and Snaith. Furthermore, assuming that the $\infty$-category contains Grassmann objects of all ranks, we prove that the projective bundle formula and the corresponding Chern-class and Whitney-sum identities hold for any oriented functor satisfying the splitting principle property. We apply the span formalism to perfectoid geometry. For perfectoid algebras $R$ with tilt $R^\flat$, we construct perfectoid cobordism, prove tilting equivalences, and compare the arc-local and $v$-local $p$-adic theories.

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BibTeX RIS

Yuki Kato. 2026-05-18. Algebraic cobordism via spans. https://arxiv.org/abs/2203.05331

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