On Newstead's Mayer-Vietoris argument in characteristic 2

Christopher Scaduto; Matthew Stoffregen

doi:10.1142/s0129167x19500654

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arXiv · 1707.06268

On Newstead's Mayer-Vietoris argument in characteristic 2

Christopher Scaduto·Matthew Stoffregen

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Abstract

Consider the moduli space of framed flat $U(2)$ connections with fixed odd determinant over a surface. Newstead combined some fundamental facts about this moduli space with the Mayer-Vietoris sequence to compute its betti numbers over any field not of characteristic two. We adapt his method in characteristic two to produce conjectural recursive formulae for the mod two betti numbers of the framed moduli space which we partially verify. We also discuss the interplay with the mod two cohomology ring structure of the unframed moduli space.

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BibTeX RIS

Christopher Scaduto, Matthew Stoffregen. 2017-07-19. On Newstead's Mayer-Vietoris argument in characteristic 2. https://doi.org/10.1142/s0129167x19500654

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