Isomorphisms between moduli stacks of vector bundles with fixed determinant

David Alfaya; Indranil Biswas; Tomás L. Gómez

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arXiv · 2511.20473

Isomorphisms between moduli stacks of vector bundles with fixed determinant

David Alfaya·Indranil Biswas·Tomás L. Gómez

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Abstract

We classify all isomorphisms between moduli stacks of vector bundles of fixed determinant on a smooth complex projective of genus at least 4. It is shown that each isomorphism between two different moduli stacks can be described as a composition of a pullback using an isomorphism of curves, dualization of vector bundles and tensoring with the pullback of a line bundle on the curve. We finally compare the 2-group of automorphisms of the moduli stack of vector bundles with the group of automorphisms of the moduli space of semistable vector bundles.

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BibTeX RIS

David Alfaya, Indranil Biswas, Tomás L. Gómez. 2025-11-25. Isomorphisms between moduli stacks of vector bundles with fixed determinant. https://arxiv.org/abs/2511.20473

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