The Frobenius map , rank 2 vector bundles and Kummer ’ s quartic surface in characteristic 2 and 3 Yves Laszlo and Christian Pauly
نویسنده
چکیده
Our interest in the diagram (1.1) comes from questions related to the action of the Frobenius map on vector bundles like e.g. surjectivity of V , density of Frobenius-stable bundles, loci of Frobenius-destabilized bundles (see [LP]). These questions are largely open when the rank of the bundles, the genus of the curve or the characteristic of the field are arbitrary. In [LP] we made use of the exceptional isomorphism D : MX → |2Θ| in the genus 2, rank 2 case and determined the equations of Ṽ when X is an ordinary curve and p = 2, which allowed us to answer the above mentioned questions. In this paper we obtain the equations of Ṽ in two more cases:
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