A criterion for the ideal of a projectively embedded toric surface to be generated by quadrics.
A Criterion for the Splitting of a Vector Bundle.
A Decomposability Criterion for Algebraic 2-Bundles on Projective Spaces.
A derivation of Kohnert's algorithm from Monk's rule.
A description based on Schubert classes of cohomology of flag manifolds
We describe the integral cohomology rings of the flag manifolds of types Bₙ, Dₙ, G₂ and F₄ in terms of their Schubert classes. The main tool is the divided difference operators of Bernstein-Gelfand-Gelfand and Demazure. As an application, we compute the Chow rings of the corresponding complex algebraic groups, recovering thereby the results of R. Marlin.
A few remarks on blowing-up and connectedness.
A filtered Bertini-type theorem.
A fixed point formula for varieties over finite fields.
A general Hilbert-Mumford criterion
Let a reductive group act on an algebraic variety . We give a Hilbert-Mumford type criterion for the construction of open -invariant subsets admitting a good quotient by .
A Hessenberg generalization of the Garsia-Procesi basis for the cohomology ring of Springer varieties.
A home-made Hartshorne-Serre correspondence.
A homological proof of a theorem by Davis, Geramita, Orecchia giving the Cayley-Bacharach theorem.
A linear bound on the t-normality of codimension two subvarieties of ...n.
A modular compactification of the general linear group.
A motivic isomorphism between two projective homogeneous varieties under the action of a group of type . (Un isomorphisme motivique entre deux variétés homogènes projectives sous l'action d'un groupe de type .)
A New Index for Polytopes.
A normal form for curves in Grassmannians.
A note on imperfect monomial curves in
A note on Schubert varieties in G / B.
A note on tangent bundles in a category with a ring object.