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We give positive formulas for the restriction of a Schubert Class to a T-fixed point in the equivariant K-theory and equivariant cohomology of the Grassmannian. Our formulas rely on a result of Kodiyalam-Raghavan and Kreiman-Lakshmibai,…

Algebraic Geometry · Mathematics 2007-05-23 V. Kreiman

We study the Schubert calculus of the affine Grassmannian Gr of the symplectic group. The integral homology and cohomology rings of Gr are identified with dual Hopf algebras of symmetric functions, defined in terms of Schur's P and…

Combinatorics · Mathematics 2011-02-07 Thomas Lam , Anne Schilling , Mark Shimozono

We provide several ingredients towards a generalization of the Littlewood-Richardson rule from Chow groups to algebraic cobordism. In particular, we prove a simple product-formula for multiplying classes of smooth Schubert varieties with…

Algebraic Geometry · Mathematics 2017-02-13 Jens Hornbostel , Nicolas Perrin

We consider the conormal bundle of a Schubert variety $S_I$ in the cotangent bundle $T^* Gr$ of the Grassmannian $Gr$ of $k$-planes in $C^n$. This conormal bundle has a fundamental class ${\kappa_I}$ in the equivariant cohomology…

Algebraic Geometry · Mathematics 2013-12-17 R. Rimanyi , V. Tarasov , A. Varchenko

We describe a "cellular" approach to the computation of the cohomology of a poset with coefficients in a presheaf. A cellular cochain complex is constructed, described explicitly and shown to compute the cohomology under certain…

Algebraic Topology · Mathematics 2016-12-13 Brent Everitt , Paul Turner

Let G be a simply-connected simple compact Lie group over the complex numbers. The affine Grassmannian is a projective ind-variety, homotopy-equivalent to the loop space of G and closely analogous to a maximal flag variety of the classical…

Algebraic Geometry · Mathematics 2007-12-19 Sara C. Billey , Stephen A. Mitchell

We give algorithms for the computation of the algebraic de Rham cohomology of open and closed algebraic sets inside projective space or other smooth complex toric varieties. The methods, which are based on Gr\"obner basis computations in…

Algebraic Geometry · Mathematics 2009-09-25 Uli Walther

We introduce a tangential theory for linked smooth manifolds of depth $1$, i.e., for spans $\mathfrak{S}=(M\overset{\pi}{\twoheadleftarrow} L\overset{\iota}{\hookrightarrow}N)$ of smooth manifolds where $\pi$ is a fibre bundle and $\iota$…

Algebraic Topology · Mathematics 2025-11-05 Ödül Tetik

We show that interlacing triangular arrays, introduced by Aggarwal-Borodin-Wheeler to study certain probability measures, can be used to compute structure constants for multiplying Schubert classes in the $K$-theory of Grassmannians, in the…

Combinatorics · Mathematics 2025-05-06 Christian Gaetz , Yibo Gao

This thesis deals with the algorithmic representation of constructible sheaves of abelian groups on the \'etale site of a variety over an algebraically closed field, as well as the explicit computation of their cohomology. We describe three…

Algebraic Geometry · Mathematics 2022-11-29 Christophe Levrat

The motivation of this work is to define cohomology classes in the space of knots that are both easy to find and to evaluate, by reducing the problem to simple linear algebra. We achieve this goal by defining a combinatorial graded cochain…

Geometric Topology · Mathematics 2016-01-14 Arnaud Mortier

This paper is concerned with local cohomology sheaves on generalized flag varieties supported in closed Schubert varieties, which carry natural structures as (mixed Hodge) D-modules. We employ Kazhdan--Lusztig theory and Saito's theory of…

Algebraic Geometry · Mathematics 2026-01-30 Michael Perlman

We show that every sheaf on the site of smooth manifolds with values in a stable (infinity,1)-category (like spectra or chain complexes) gives rise to a differential cohomology diagram and a homotopy formula, which are common features of…

K-Theory and Homology · Mathematics 2013-11-15 Ulrich Bunke , Thomas Nikolaus , Michael Völkl

In this article, we use the Bruhat and Schubert cells to calculate the cellular homology of the maximal compact subgroup $K$ of a connected semisimple Lie group $G$ whose Lie algebra is a split real form. We lift to the maximal compact…

Algebraic Topology · Mathematics 2024-09-02 Mauro Patrão , Ricardo Sandoval

A theorem of the first author states that the cotangent bundle of the type $A$ Grassmannian variety can be embedded as an open subset of a smooth Schubert variety in a two-step affine partial flag variety. We extend this result to cotangent…

Algebraic Geometry · Mathematics 2015-05-19 V. Lakshmibai , Vijay Ravikumar , William Slofstra

The Drinfel'd Lagrangian Grassmannian compactifies the space of algebraic maps of fixed degree from the projective line into the Lagrangian Grassmannian. It has a natural projective embedding arising from the canonical embedding of the…

Algebraic Geometry · Mathematics 2008-06-05 James Ruffo

In this paper we show that, besides the usual calculus involving K\"ahler differentials, it is also possible to define conical calculus on schemes and perfectoid spaces; this can be done via a stratification process. Following some ideas…

Algebraic Topology · Mathematics 2020-04-28 Manuel Norman

In this paper, we mainly build up the theory of sheaf-correspondence filtered spaces and stratified de Rham complexes for studying singular spaces. We prove the finiteness of a stratified de Rham cohomology and obtain its isomorphism to…

Algebraic Geometry · Mathematics 2025-05-02 Jiaming Luo , Shirong Li

In this paper, we study the T_w-equivariant cohomology of the weighted Grassmannians wGr(d,n) introduced by Corti-Reid where T_w is the n-dimensional torus that naturally acts on wGr(d,n). We introduce the equivariant weighted Schubert…

Algebraic Topology · Mathematics 2013-10-30 Hiraku Abe , Tomoo Matsumura

We compute the Hochschild-Kostant-Rosenberg decomposition of the Hochschild cohomology of generalised Grassmannians, i.e. partial flag varieties associated to maximal parabolic subgroups in a simple algebraic group. We explain how the…

Algebraic Geometry · Mathematics 2023-05-16 Pieter Belmans , Maxim Smirnov