Virtual classes and virtual motives of Quot schemes on threefolds

Andrea T. Ricolfi

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arXiv · 1906.02557

Virtual classes and virtual motives of Quot schemes on threefolds

Andrea T. Ricolfi

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Abstract

For a simple, rigid vector bundle $F$ on a Calabi-Yau $3$-fold $Y$, we construct a symmetric obstruction theory on the Quot scheme $\textrm{Quot}_Y(F,n)$, and we solve the associated enumerative theory. We discuss the case of other $3$-folds. Exploiting the critical structure on $\textrm{Quot}_{\mathbb A^3}(\mathscr O^r,n)$, we construct a virtual motive (in the sense of Behrend-Bryan-Szendrői) for $\textrm{Quot}_Y(F,n)$ for an arbitrary vector bundle $F$ on a smooth $3$-fold $Y$. We compute the associated motivic partition function. We obtain new examples of higher rank (motivic) Donaldson-Thomas invariants.

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BibTeX RIS

Andrea T. Ricolfi. 2020-04-19. Virtual classes and virtual motives of Quot schemes on threefolds. https://arxiv.org/abs/1906.02557

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