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Given a GKM$_3$ action of a torus $K$ on a manifold $M$ with GKM graph $\Gamma$, we show that for any extension of $\Gamma$ to an abstract GKM graph the corresponding restriction map in equivariant graph cohomology is surjective. While the…

Algebraic Topology · Mathematics 2026-04-16 Oliver Goertsches , Grigory Solomadin

In topology there is a theorem of Atiyah, concerning K-theory of classifying space of connected compact Lie group. We consider an algebraic analogue of this theorem. We prove that for a split reductive algebraic group G over a field there…

K-Theory and Homology · Mathematics 2011-11-22 Alisa Knizel , Alexander Neshitov

In this paper we consider a class of connected closed $G$-manifolds with a non-empty finite fixed point set, each $M$ of which is totally non-homologous to zero in $M_G$ (or $G$-equivariantly formal), where $G={\Bbb Z}_2$. With the help of…

Algebraic Topology · Mathematics 2009-02-17 Bo Chen , Zhi Lü

We construct differential equivariant K-theory of representable smooth orbifolds as a ring valued functor with the usual properties of a differential extension of a cohomology theory. For proper submersions (with smooth fibres) we construct…

K-Theory and Homology · Mathematics 2015-07-16 Ulrich Bunke , Thomas Schick

In paper arXiv:1109.6031 the author introduced stable formality quasi-isomorphisms and described the set of its homotopy classes. This result can be interpreted as a complete description of formal quantization procedures. In this note we…

Quantum Algebra · Mathematics 2011-11-14 Vasily Dolgushev

Let G be a compact Lie group and LG its associated loop group. The main result of this manuscript is a surjectivity theorem from the equivariant K-theory of a Hamiltonian LG-space onto the integral K-theory of its Hamiltonian LG-quotient.…

Symplectic Geometry · Mathematics 2007-12-20 Megumi Harada , Paul Selick

The equivariant movability of topological spaces with an action of a given topological group $G$ is considered. In particular, the equivariant movability of topological groups is studied. It is proved that a second countable group $G$ is…

General Topology · Mathematics 2023-08-07 Pavel S. Gevorgyan

If $(R,I)$ is a henselian pair with an action of a finite group $G$ and $n\ge 1$ is an integer coprime to $|G|$ and such that $n\cdot |G|\in R^*$, then the reduction map of mod-$n$ equivariant $K$-theory spectra \[…

K-Theory and Homology · Mathematics 2020-03-25 Niko Naumann , Charanya Ravi

Given a spin rational homology sphere $Y$ equipped with a $\mathbb{Z}/m$-action preserving the spin structure, we use the Seiberg--Witten equations to define equivariant refinements of the invariant $\kappa(Y)$ from \cite{Man14}, which take…

Geometric Topology · Mathematics 2025-10-14 Imogen Montague

Let $M=G/K$ be a Hermitian symmetric space of noncompact type. We provide a way of constructing $K$-equivariant embeddings from $M$ to its tangent space $T_oM$ at the origin by using the polarity of the $K$-action. As an application, we…

Differential Geometry · Mathematics 2021-09-07 Takahiro Hashinaga , Toru Kajigaya

We compute the equivariant $K$-homology of the classifying space for proper actions, for compact 3-dimensional hyperbolic reflection groups. This coincides with the topological $K$-theory of the reduced $C^\ast$-algebra associated to the…

K-Theory and Homology · Mathematics 2020-08-05 Jean-François Lafont , Ivonne J. Ortiz , Alexander Rahm , Rubén J. Sánchez-García

In this article, we generalize to the case of measured quantum groupoids on a finite basis some important results concerning equivariant Kasparov theory for actions of locally compact quantum groups [S. Baaj and G. Skandalis, 1989, 1993].…

Operator Algebras · Mathematics 2017-06-28 Jonathan Crespo

Let $\Uq$ be a quantum group. Regarding a (noncommutative) space with $\Uq$-symmetry as a $\Uq$-module algebra $A$, we may think of equivariant vector bundles on $A$ as projective $A$-modules with compatible $\Uq$-action. We construct an…

Quantum Algebra · Mathematics 2009-12-21 G. I. Lehrer , R. B. Zhang

In this paper, we study the equivariant homotopy type of a connected sum of linear actions on complex projective planes defined by Hambleton and Tanase. These actions are constructed for cyclic groups of odd order. We construct cellular…

Algebraic Topology · Mathematics 2021-09-28 Samik Basu , Pinka Dey , Aparajita Karmakar

We describe the $C_2$-equivariant homotopy type of the space of commuting n-tuples in the stable unitary group in terms of Real K-theory. The result is used to give a complete calculation of the homotopy groups of the space of commuting…

Algebraic Topology · Mathematics 2019-04-24 Simon Gritschacher , Markus Hausmann

We construct geometric models for classifying spaces of linear algebraic groups in G-equivariant motivic homotopy theory, where G is a tame group scheme. As a consequence, we show that the equivariant motivic spectrum representing the…

K-Theory and Homology · Mathematics 2020-09-16 Marc Hoyois

A cornerstone of algebraic K-theory is the equivalence between the K-theory machines of May, Segal, and Elmendorf and Mandell. Equivariant algebraic K-theory enriches the theory with group actions, making it more powerful and complex. There…

Algebraic Topology · Mathematics 2025-11-12 Donald Yau

The purpose of this paper is to prove an equivariant Riemann-Roch theorem for schemes or algebraic spaces with an action of a linear algebraic group $G$. For a $G$-space $X$, this theorem gives an isomorphism between a completion of the…

Algebraic Geometry · Mathematics 2016-09-07 Dan Edidin , William Graham

This paper explores topological complexity in the finite equivariant setting. We first define and study an equivariant version of Tanaka's combinatorial complexity for finite topological spaces. We explore the relationships between this…

Algebraic Topology · Mathematics 2022-01-12 Rebecca Bell , Allison N. Eckert , Ryan M. Pesak , Avery Schweitzer

In this paper, we consider translators (for the mean curvature flow) given by a graph of a function on a symmetric space $G/K$ of compact type which is invariant under a hyperpolar action on $G/K$. First, in the case of $G/K=SO(n+1)/SO(n)$,…

Differential Geometry · Mathematics 2023-10-16 Tomoki Fujii , Naoyuki Koike