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arXiv · 1310.0895

A Thom-Porteous formula for connective K-theory using algebraic cobordism

Thomas Hudson
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Abstract

We prove a formula for the push-forward class of Bott-Samelson resolutions in the algebraic cobordism ring of the flag bundle. We specialise our formula to connective K-theory providing a geometric interpretation to the double beta-polynomials of Fomin and Kirillov by computing the fundamental classes of Schubert varieties. As a corollary we obtain a Thom-Porteous formula generalising those of the Chow ring and of the Grothendieck ring of vector bundles.

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Thomas Hudson. 2013-10-03. A Thom-Porteous formula for connective K-theory using algebraic cobordism. https://doi.org/10.1017/is014005031jkt266

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