Spectral curves of operators with elliptic coefficients.
In questa nota si danno dei criteri per la stabilità di fasci di quartiche piane.
This note gives a survey of some recent results on the stable reduction of covers of the projective line branched at three points.
The subject of this article is the notion of -spin structure: a line bundle whose th power is isomorphic to the canonical bundle. Over the moduli functor of smooth genus- curves, -spin structures form a finite torsor under the group of -torsion line bundles. Over the moduli functor of stable curves, -spin structures form an étale stack, but both the finiteness and the torsor structure are lost.In the present work, we show how this bad picture can be definitely improved just by placing...