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arXiv · 2412.05375

On the essential dimension of symplectic vector bundles over curves

Ajneet Dhillon·Sayantan Roy Chowdhury
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Abstract

Let $X$ be a smooth geometrically connected projective curve of genus at least 2 over a field of characteristic zero. We compute the essential dimension of the moduli stack of symplectic bundles over $X$. Unlike the case of vector bundles, we are able to precisely compute the essential dimension as the generic gerbe of the moduli stack has period 2 over it's moduli space.

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Ajneet Dhillon, Sayantan Roy Chowdhury. 2024-12-06. On the essential dimension of symplectic vector bundles over curves. https://arxiv.org/abs/2412.05375

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