Results 31 to 40 of about 1,003 (79)

A note on the CR cohomology of Levi-Flat minimal orbits in complex flag manifolds [PDF]

, 2005
We prove a relation between the $\bar\partial_M$ cohomology of a minimal orbit $M$ of a real form $G_0$ of a complex semisimple Lie group $G$ in a flag manifold $G/Q$ and the Dolbeault cohomology of the Matsuki dual open orbit $X$ of the complexification
Altomani, Andrea
core   +4 more sources

Coordinate rings of regular nilpotent Hessenberg varieties in the open opposite schubert cell

Forum of Mathematics, Sigma
Dale Peterson has discovered a surprising result that the quantum cohomology ring of the flag variety $\operatorname {\mathrm {GL}}_n({\mathbb {C}})/B$ is isomorphic to the coordinate ring of the intersection of the Peterson variety ...
Tatsuya Horiguchi, Tomoaki Shirato
doaj   +1 more source

Geometrization of the Satake transform for mod p Hecke algebras

Forum of Mathematics, Sigma
We geometrize the mod p Satake isomorphism of Herzig and Henniart–Vignéras using Witt vector affine flag varieties for reductive groups in mixed characteristic. We deduce this as a special case of a formula, stated in terms of the geometry of generalized
Robert Cass, Yujie Xu
doaj   +1 more source

Combinatorial formulas for shifted dual stable Grothendieck polynomials

Forum of Mathematics, Sigma
The K-theoretic Schur P- and Q-functions $G\hspace {-0.2mm}P_\lambda $ and $G\hspace {-0.2mm}Q_\lambda $ may be concretely defined as weight-generating functions for semistandard shifted set-valued tableaux.
Joel Lewis, Eric Marberg
doaj   +1 more source

Cohomological consequences of the pattern map [PDF]

, 2014
Billey and Braden defined maps on flag manifolds that are the geometric counterpart of permutation patterns. A section of their pattern map is an embedding of the flag manifold of a Levi subgroup into the full flag manifold.
Adeyemo, Praise, Sottile, Frank
core  

Integral models of Shimura varieties with parahoric level structure, II

Forum of Mathematics, Pi
We construct integral models of Shimura varieties of abelian type with parahoric level structure over odd primes. These models are étale locally isomorphic to corresponding local models.
Mark Kisin, Georgios Pappas, Rong Zhou
doaj   +1 more source

An inverse Grassmannian Littlewood–Richardson rule and extensions

Forum of Mathematics, Sigma
Chow rings of flag varieties have bases of Schubert cycles $\sigma _u $ , indexed by permutations. A major problem of algebraic combinatorics is to give a positive combinatorial formula for the structure constants of this basis.
Oliver Pechenik, Anna Weigandt
doaj   +1 more source

Algebraic hyperbolicity of very general hypersurfaces in homogeneous varieties [PDF]

Épijournal de Géométrie Algébrique
We generalize techniques by Coskun, Riedl, and Yeong, and obtain an almost optimal bound on the degree for the algebraic hyperbolicity of very general hypersurfaces in rational homogeneous varieties.
Lucas Mioranci
doaj   +1 more source

Quantum K theory of Grassmannians, Wilson line operators and Schur bundles

Forum of Mathematics, Sigma
We prove a ‘Whitney’ presentation, and a ‘Coulomb branch’ presentation, for the torus equivariant quantum K theory of the Grassmann manifold $\mathrm {Gr}(k;n)$ , inspired from physics, and stated in an earlier paper.
Wei Gu, Leonardo Mihalcea, Eric Sharpe, Hao Zou   +3 more
doaj   +1 more source

Smooth locus of twisted affine Schubert varieties and twisted affine Demazure modules

Forum of Mathematics, Sigma
Let ${\mathscr {G}} $ be a special parahoric group scheme of twisted type over the ring of formal power series over $\mathbb {C}$ , excluding the absolutely special case of $A^{(2)}_{2\ell }$ .
Marc Besson, Jiuzu Hong
doaj   +1 more source