# A K-theoretic Fulton class

@article{Thomas2018AKF, title={A K-theoretic Fulton class}, author={Richard P. Thomas}, journal={arXiv: Algebraic Geometry}, year={2018} }

Fulton defined classes in the Chow group of a quasi-projective scheme $M$ which reduce to its Chern classes when $M$ is smooth. When $M$ has a perfect obstruction theory, Siebert gave a formula for its virtual cycle in terms of its total Fulton class.
We describe K-theory classes on $M$ which reduce to the exterior algebra of differential forms when $M$ is smooth. When $M$ has a perfect obstruction theory, we give a formula for its K-theoretic virtual structure sheaf in terms of these classes.

## 5 Citations

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In Maulik and Thomas (in preparation) the Vafa–Witten theory of complex projective surfaces is lifted to oriented C∗-equivariant cohomology theories. Here we study the K -theoretic refinement. It…

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Abstract We exploit the critical structure on the Quot scheme $\text {Quot}_{{{\mathbb {A}}}^3}({\mathscr {O}}^{\oplus r}\!,n)$, in particular the associated symmetric obstruction theory, in order to…

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