The Brauer group of moduli spaces of vector bundles over a real curve

Biswas, Indranil; Hoffmann, Norbert; Hogadi, Amit; Schmitt, Alexander

doi:10.1090/S0002-9939-2011-10837-2

The Brauer group of moduli spaces of vector bundles over a real curve
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by Indranil Biswas, Norbert Hoffmann, Amit Hogadi and Alexander H. W. Schmitt

Proc. Amer. Math. Soc. 139 (2011), 4173-4179

DOI: https://doi.org/10.1090/S0002-9939-2011-10837-2

Published electronically: April 5, 2011

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Abstract:

Let $X$ be a geometrically connected smooth projective curve of genus $g_X \geq 2$ over $\mathbb {R}$. Let $M(r, \xi )$ be the coarse moduli space of geometrically stable vector bundles $E$ over $X$ of rank $r$ and determinant $\xi$, where $\xi$ is a real point of the Picard variety $\underline {\mathrm {Pic}}^d( X)$. If $g_X = r = 2$, then let $d$ be odd. We compute the Brauer group of $M(r,\xi )$.

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