Morse theory and toric vector bundles

David Treumann

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arXiv · 1010.4071

Morse theory and toric vector bundles

David Treumann

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Abstract

Morelli's computation of the K-theory of a toric variety X associates a polyhedrally constructible function on a real vector space to every equivariant vector bundle E on X. The coherent-constructible correspondence lifts Morelli's constructible function to a complex of constructible sheaves kappa(E). We show that certain filtrations of the cohomology of kappa(E) coming from Morse theory coincide with the Klyachko filtrations of the generic stalk of E. We give Morse-theoretic (i.e. microlocal) conditions for a complex of constructible sheaves to correspond to a vector bundle, and to a nef vector bundle.

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BibTeX RIS

David Treumann. 2010-10-19. Morse theory and toric vector bundles. https://arxiv.org/abs/1010.4071

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