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Related papers: Twisted Orbifold K-Theory

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In this article, we study the twisting procedure of orbifold cohomology. We introduce local system and construct twisted orbifold cohomology. Then, we generalize Vafa-Witten's notion of discrete torsion to general orbifold and examine its…

Algebraic Geometry · Mathematics 2007-05-23 Yongbin Ruan

Using methods of KK-theory, we generalize Poincare duality to the framework of twisted K-theory.

K-Theory and Homology · Mathematics 2007-05-23 Jean-Louis Tu

We study the GKM theory for a equivariant stratified space having orbifold structures in tis successive quotients. Then, we introduce the notion of an \emph{almost simple polytope}, as well as a \emph{divisive toric variety} generalizing…

Algebraic Topology · Mathematics 2020-12-03 Soumen Sarkar , Jongbaek Song

In this paper, we develop differential twisted K-theory and define a twisted Chern character on twisted K-theory which depends on a choice of connection and curving on the twisting gerbe. We also establish the general Riemann-Roch theorem…

K-Theory and Homology · Mathematics 2008-09-28 Alan L. Carey , Jouko Mickelsson , Bai-Ling Wang

We compare different algebraic structures in twisted equivariant K-Theory for proper actions of discrete groups. After the construction of a module structure over untwisted equivariant K-Theory, we prove a completion Theorem of Atiyah-Segal…

K-Theory and Homology · Mathematics 2019-01-15 Noe Barcenas , Mario Velasquez

We present a largely self contained account on the K-theory of a weighted smooth projective curve over an algebraically closed field. In particular, we discuss the weighted version of divisor theory, Euler form, and Riemann-Roch theorem.…

Algebraic Geometry · Mathematics 2017-02-14 Helmut Lenzing

We discuss twisted cohomology, not just for ordinary cohomology but also for $K$-theory and other exceptional cohomology theories, and discuss several of the applications of these in mathematical physics. Our list of applications is by no…

Algebraic Topology · Mathematics 2024-01-09 Jonathan Rosenberg

We determine the class of finite T_0-spaces allowing for a universal coefficient theorem computing equivariant KK-theory by filtrated K-theory.

Operator Algebras · Mathematics 2012-02-21 Rasmus Bentmann , Manuel Köhler

The goal of the present paper is the calculation of the equivariant twisted K-theory of a compact Lie group which acts on itself by conjugations, and elements of a TQFT-structure on the twisted K-groups. These results are originally due to…

K-Theory and Homology · Mathematics 2007-05-23 Ulrich Bunke , Ingo Schroeder

Twisted K-theory has received much attention recently in both mathematics and physics. We describe some models of twisted K-theory, both topological and geometric. Then we state a theorem which relates representations of loop groups to…

Algebraic Topology · Mathematics 2007-05-23 Daniel S. Freed

This paper contains two results concerning the equivariant K-theory of toric varieties. The first is a formula for the equivariant K-groups of an arbitrary affine toric variety, generalizing the known formula for smooth ones. In fact, this…

K-Theory and Homology · Mathematics 2008-09-22 Suanne Au , Mu-wan Huang , Mark E. Walker

In this short note we discuss discrete torsion in orientifolds. In particular, we apply the physical understanding of discrete torsion worked out several years ago, as group actions on B fields, to the case of orientifolds, and recover some…

High Energy Physics - Theory · Physics 2011-03-28 E. Sharpe

We give a short introduction to the theory of twisted Alexander polynomials of a 3--manifold associated to a representation of its fundamental group. We summarize their formal properties and we explain their relationship to twisted…

Geometric Topology · Mathematics 2010-02-05 Stefan Friedl , Stefano Vidussi

We describe Universal Coefficient Theorems for the equivariant Kasparov theory for C*-algebras with an action of the group of integers or over a unique path space, using KK-valued invariants. We compare the resulting classification up to…

K-Theory and Homology · Mathematics 2020-11-04 Ralf Meyer

In this paper we construct an explicit geometric model for the group of gerbes over an orbifold $X$. We show how from its curvature we can obtain its characteristic class in $H^3(X)$ via Chern-Weil theory. For an arbitrary gerbe $\LL$, a…

Algebraic Topology · Mathematics 2007-05-23 Ernesto Lupercio , Bernardo Uribe

Let G be a compact, simply connected Lie group. We develop a `quantization functor' from pre-quantized quasi-Hamiltonian G-spaces at level k to the fusion ring (Verlinde algebra) R_k(G). The quantization Q(M) is defined as a push-forward in…

Differential Geometry · Mathematics 2013-12-05 E. Meinrenken

In this paper we define twisted equivariant K-theory for actions of Lie groupoids. For a Bredon-compatible Lie groupoid, this defines a periodic cohomology theory on the category of finite CW-complexes with equivariant stable projective…

Algebraic Topology · Mathematics 2011-05-18 Jose Cantarero

Let $\ix$ be a smooth Deligne-Mumford stack over the complex numbers. One can define twisted orbifold Gromov-Witten invariants of $\ix$ by considering multiplicative invertible characteristic classes of various bundles on the moduli spaces…

Algebraic Geometry · Mathematics 2016-07-15 Valentin Tonita

The concept of orbifolds should unify differential geometry with equivariant homotopy theory, so that orbifold cohomology should unify differential cohomology with proper equivariant cohomology theory. Despite the prominent role that…

Algebraic Topology · Mathematics 2020-09-29 Hisham Sati , Urs Schreiber

Replaces Previous version. Includes comments on poincare duality for twisted equivariant in the context of proper and discrete actions and the Baum-Connes Conjecture. We use a spectral sequence proposed by C. Dwyer and previous work by…

K-Theory and Homology · Mathematics 2013-08-23 Noe Barcenas , Mario Velasquez