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Related papers: Modular equivariant formality

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Given an action of an affine algebraic group with only trivial characters on a factorial variety, we ask for categorical quotients. We characterize existence in the category of algebraic varieties. Moreover, allowing constructible sets as…

Algebraic Geometry · Mathematics 2013-05-15 I. V. Arzhantsev , D. Celik , J. Hausen

Let $\Oq(G)$ be the algebra of quantized functions on an algebraic group $G$ and $\Oq(B)$ its quotient algebra corresponding to a Borel subgroup $B$ of $G$. We define the category of sheaves on the "quantum flag variety of $G$" to be the…

Quantum Algebra · Mathematics 2007-11-13 Erik Backelin , Kobi Kremnizer

For a finite abelian group $G$, we compute the $G$-equivariant formal group law corresponding to the $G$-equivariant complex cobordism spectrum with its canonical complex orientation.

Algebraic Topology · Mathematics 2015-03-31 William C. Abram

We associate a bivariant theory to any suitable oriented Borel-Moore homology theory on the category of algebraic schemes or the category of algebraic G-schemes. Applying this to the theory of algebraic cobordism yields operational…

Algebraic Geometry · Mathematics 2016-01-20 José Luis González , Kalle Karu

We use the formal affine Demazure algebra to construct an explicit Leray-Hirsch Theorem for torus equivariant oriented cohomology of flag varieties. We then generalize the Borel model of such theory to partial flag varieties.

Algebraic Geometry · Mathematics 2025-06-13 J. Matthew Douglass , Changlong Zhong

If a closed orientable manifold (resp. rational Poincar\'e duality space) $X$ receives a map $Y \to X$ from a formal manifold (resp. space) $Y$ that hits a fundamental class, then $X$ is formal. The main technical ingredient in the proof…

Algebraic Topology · Mathematics 2023-06-22 Aleksandar Milivojevic , Jonas Stelzig , Leopold Zoller

Let $\XR$ be a (generalized) flag manifold of a non-compact real semisimple Lie group $\GR$, where $\XR$ and $\GR$ have complexifications X and G. We investigate the problem of constructing a graded star product on $Pol(T^*\XR)$ which…

Quantum Algebra · Mathematics 2007-05-23 Ranee Brylinski

Let $G/H$ be a homogeneous variety, and let $X$ be a $G$-equivariant embedding of $G/H$such that the number of $G$-orbits in $X$ is finite. We show that the equivariant Borel-Moore homology of $X$ has a filtration with associated graded…

Algebraic Geometry · Mathematics 2019-06-06 Aram Bingham , Mahir Bilen Can , Yıldıray Ozan

We give Leray-Borel-type descriptions for the mod-$2$ and the rational equivariant cohomology rings of the real and the oriented flag manifolds under the canonical torus or 2-torus actions.

Algebraic Topology · Mathematics 2019-01-14 Chen He

We prove an analogue of the Borel-Bott-Weil theorem in equivariant KK-theory by constructing certain canonical equivariant correspondences between minimal flag varieties G/B, with G a complex semisimple Lie group.

K-Theory and Homology · Mathematics 2014-04-10 Heath Emerson , Robert Yuncken

Let X be a smooth complex algebraic variety. Morgan [Mor78] showed that the rational homotopy type of X is a formal consequence of the differential graded algebra defined by the first term of its weight spectral sequence. In the present…

Algebraic Geometry · Mathematics 2014-11-26 J. Cirici , F. Guillén

We discuss the formal aspects of the factorial polynomials and of the associated series. We develop the theory using the formalism of quasi-monomials and prove the usefulness of the method for the solutions of nontrivial difference…

Analysis of PDEs · Mathematics 2011-07-21 D. Babusci , G. Dattoli , M. Carpanese

There are (at least) two different approaches to define equivariant analogue of the Euler charateristic for a space with a finite group action. The first one defines it as an element of the Burnside ring of the group. The second approach…

Algebraic Geometry · Mathematics 2016-05-11 S. M. Gusein-Zade , I. Luengo , A. Melle-Hernández

In this note we present an analogue of equivariant formality in $K$-theory and show that it is equivalent to equivariant formality \emph{\`a la} Goresky-Kottwitz-MacPherson. We also apply this analogue to give alternative proofs of…

Algebraic Topology · Mathematics 2019-02-13 Chi-Kwong Fok

For an abelian category with a Serre duality and a finite group action, we compute explicitly the Serre duality on the category of equivariant objects. Special cases and examples are discussed. In particular, an abelian category with a…

Rings and Algebras · Mathematics 2017-10-10 Xiao-Wu Chen

We show that the Borel-equivariant derived category of sheaves on the flag variety of a complex reductive group is equivalent to the perfect derived category of dg modules over the extension algebra of the direct sum of the simple…

Representation Theory · Mathematics 2008-09-30 Olaf M. Schnürer

In this paper, the formal derivative operator defined with respect to context-free grammars is used to prove some properties about binomial coefficients and multifactorial numbers. In addition, we extend the formal derivative operator to…

Combinatorics · Mathematics 2018-08-21 Juan Triana , Rodrigo De Castro

Taking symmetric powers of varieties can be seen as a functor from the category of varieties to the category of varieties with an action by the symmetric group. We study a corresponding map between the Grothendieck groups of these…

Algebraic Geometry · Mathematics 2019-04-16 Daniel Bergh

Let $i: \mathrm{L} \hookrightarrow \mathrm{X}$ be a compact K\"{a}hler Lagrangian in a holomorphic symplectic variety $\mathrm{X}/\mathbf{C}$. We use deformation quantisation to show that the endomorphism differential graded algebra…

Algebraic Geometry · Mathematics 2026-04-09 Borislav Mladenov

In this note, we provide a proof of the existence and complete classification of $G$-invariant star products with quantum momentum maps on Poisson manifolds by means of an equivariant version of the formality theorem.

Quantum Algebra · Mathematics 2025-02-26 Chiara Esposito , Ryszard Nest , Jonas Schnitzer , Boris Tsygan