Singularities of polar curves
Singularities of Quotients by Vector Fields in Characteristic p.
Singularities of the moduli spaces of certain abelian surfaces
Singularities of theta divisors and the geometry of
We study the codimension two locus in consisting of principally polarized abelian varieties whose theta divisor has a singularity that is not an ordinary double point. We compute the class for every . For , this turns out to be the locus of Jacobians with a vanishing theta-null. For , via the Prym map we show that has two components, both unirational, which we describe completely. We then determine the slope of the effective cone of and show that the component of the Andreotti-Mayer...
Singularities on complete algebraic varieties
We prove that any finite set of n-dimensional isolated algebraic singularities can be afforded on a simply connected projective variety.
Singularities on flag spaces
Singularities with exact Poincaré complex but not quasihomogeneous.
We give examples of complete intersections in C3 with exact Poincaré complex but not quasihomogeneous using the classification of C.T.C. and the algorithm of Mora.
Singularity of the moduli space of stable bundles on surfaces
Skew fields of noncommutative rational functions (preliminary version)
Skew-Symmetric Vanishing Lattices and Their Monodromy Groups.
Skew-Symmetric Vanishing Lattices and Their Monodromy Groups. II.
-equivariant polynomial automorphisms of the binary forms
We consider the space of binary forms of degree denoted by . We will show that every polynomial automorphism of which commutes with the linear -action and which maps the variety of forms with pairwise distinct zeroes into itself, is a multiple of the identity on .
SL2 actions and cohomology of Schubert varieties
SL2-triplet associé à un polynôme homogène.
Slices and transfers.
Slices étales
Slope filtration of quasi-unipotent overconvergent -isocrystals
We study local properties of quasi-unipotent overconvergent -isocrystals on a curve over a perfect field of positive characteristic . For a --module over the Robba ring , we define the slope filtration for Frobenius structures. We prove that an overconvergent -isocrystal is quasi-unipotent if and only if it has the slope filtration for Frobenius structures locally at every point on the complement of the curve.
Slope filtrations revisited.
Slopes of effective divisors on the moduli space of stable curves.
Slopes of powers of Frobenius on crystalline cohomology