FROBENIUS-UNSTABLE BUNDLES AND p-CURVATURE
نویسنده
چکیده
We use the theory of p-curvature of connections to analyze stable vector bundles of rank 2 on curves of genus 2 which pull back to unstable bundles under the Frobenius morphism. We take two approaches, first using explicit formulas for p-curvature to analyze low-characteristic cases, and then using degeneration techniques to obtain an answer for a general curve by degenerating to an irreducible rational nodal curve, and applying the results of [13] and [15]. We also apply our explicit formulas to give a new description of the strata of curves of genus 2 of different p-rank.
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