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Two components of the boundary of the compactification of the variety of instantons

Nicolas Perrin
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Abstract

We study two components of the boundary of the compactification of the variety I_3 of instantons of degree three. We use the desciption of I_3 as symetric (involutive) cubo-cubic transforms deduced from the Beilinson monade. It involves some geometry of curves and surfaces in P^3. This allows us to distinguish two irreducible components which are in the closure of involutive cubo-cubic transforms. It gives us two irreducible components of the boundary of I_3. Moreover, we show that the cubo-cubic transforms of one of these components are the inverse of the other one.

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Nicolas Perrin. 2001-10-12. Two components of the boundary of the compactification of the variety of instantons. https://arxiv.org/abs/math/9901011

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