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Deformations des extensions larges de faisceaux

Jean-Marc Drezet
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Abstract

Let X be a projective smooth irreducible polarized variety over the field of complex numbers. Typical examples of wide extensions are vector bundles E that have a subsheaf F whose slope is much bigger than the slope of E/F, and such that F and E/F are stable. We study the deformations of such bundles. The case of unstable rank 2 bundles has been considered by S.A. Stromme on P_2, and by C. Banica on P_3. We build moduli spaces of wide extensions, and if the dimension of X is greater than 2, it may even happen that we obtain fine moduli spaces.

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Jean-Marc Drezet. 2002-01-15. Deformations des extensions larges de faisceaux. https://arxiv.org/abs/math/0201125

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