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Related papers: Bivariant K-theory via correspondences

200 papers

Fulton and MacPherson introduced the notion of bivariant theories and Grothendieck transformations related to Riemann-Roch-theorems. But there are many situations, where such a bivariant theory or a corresponding Grothendieck transformation…

Algebraic Geometry · Mathematics 2007-05-23 Joerg Schuermann

There is an equivalence relation on the set of smooth maps of a manifold into the stable unitary group, defined using a Chern-Simons type form, whose equivalence classes form an abelian group under ordinary block sum of matrices. This…

K-Theory and Homology · Mathematics 2012-11-20 Thomas Tradler , Scott O. Wilson , Mahmoud Zeinalian

We describe a variant of K-theory for spaces with involution, built from vector bundles which are sent to their negative under the involution.

K-Theory and Homology · Mathematics 2007-05-23 Michael Atiyah , Michael Hopkins

We define the filtrated K-theory of a C*-algebra over a finite topological space X and explain how to construct a spectral sequence that computes the bivariant Kasparov theory over X in terms of filtrated K-theory. For finite spaces with…

Operator Algebras · Mathematics 2015-10-23 Ralf Meyer , Ryszard Nest

We extend topological T-duality to the case of general circle bundles. In this setting we prove existence and uniqueness of T-duals. We then show that T-dual spaces have isomorphic twisted cohomology, twisted $K$-theory and Courant…

Differential Geometry · Mathematics 2014-11-07 David Baraglia

Let $X$ be the wonderful compactification of a complex adjoint symmetric space $G/K$ such that $rk(G/K)=rk(G)-rk(K)$. We show how to extend equivariant vector bundles on $G/K$ to equivariant vector bundles on $X$, generated by their global…

Algebraic Geometry · Mathematics 2007-05-23 Michel Brion

Let $\Delta$ be a trivial knot in the three-sphere. For every finite cyclic group $G$ of odd order, we construct a $G$-equivariant Khovanov homology with coefficients in the filed $\F_{2}$. This homology is an invariant of links up to…

Geometric Topology · Mathematics 2007-05-23 Nafaa Chbili

The Kechris-Pestov-Todor\v{c}evi\'c correspondence (KPT-correspondence for short) is a surprising correspondence between model theory, combinatorics and topological dynamics. In this paper we present a categorical re-interpretation of (a…

Category Theory · Mathematics 2020-09-21 Dragan Mašulović

We study invariants associated to Smale spaces obtained from an expanding endomorphism on a (closed connected Riemannian) flat manifold. Specifically, the relevant invariants are the $K$-theory of the associated $C^*$-algebras and Putnam's…

Equivariant quantization is a new theory that highlights the role of symmetries in the relationship between classical and quantum dynamical systems. These symmetries are also one of the reasons for the recent interest in quantization of…

Differential Geometry · Mathematics 2015-05-18 N. Poncin , F. Radoux , R. Wolak

In this paper we identify QD(A,B), the quasidiagonal classes in KK_1(A,B), in terms of K_*(A) and K_*(B), and we use these results in various applications. Here is our central result. Theorem: Suppose that A is in the category of separable…

Operator Algebras · Mathematics 2007-05-23 Claude Schochet

In this article we describe the $G\times G$-equivariant $K$-ring of $X$, where $X$ is a regular compactification of a connected complex reductive algebraic group $G$. Furthermore, in the case when $G$ is a semisimple group of adjoint type,…

Algebraic Geometry · Mathematics 2007-06-12 V. Uma

We consider twisted equivariant K--theory for actions of a compact Lie group $G$ on a space $X$ where all the isotropy subgroups are connected and of maximal rank. We show that the associated rational spectral sequence \`a la Segal has a…

Algebraic Topology · Mathematics 2019-10-01 Alejandro Adem , José Cantarero , José Manuel Gómez

Group lattices (Cayley digraphs) of a discrete group are in natural correspondence with differential calculi on the group. On such a differential calculus geometric structures can be introduced following general recipes of noncommutative…

Mathematical Physics · Physics 2015-06-26 Aristophanes Dimakis , Folkert Muller-Hoissen

In this paper it is demonstrated that the Kasparov pairing is continuous with respect to the natural topology on the Kasparov groups, so that a KK-equivalence is an isomorphism of topological groups. In addition, we demonstrate that the…

Operator Algebras · Mathematics 2016-09-07 Claude Schochet

We construct a model of differential K-theory, using the geometrically defined Chern forms, whose cocycles are certain equivalence classes of maps into the Grassmannians and unitary groups. In particular, we produce the circle-integration…

K-Theory and Homology · Mathematics 2015-07-08 Thomas Tradler , Scott O. Wilson , Mahmoud Zeinalian

Biinvariant diagonal classes give rise to right inverses of the Kirwan map. By means of multivalued perturbations of the gradient flow equation such classes are constructed explicitly for $S^1$-Hamiltonian spaces. Moreover, the notion of…

Symplectic Geometry · Mathematics 2016-05-10 Andratx Bellmunt

For $G$ a finite group, a normalized 2-cocycle $\alpha\in Z^{2}\big(G,{\mathbb S}^{1}\big)$ and $X$ a $G$-space on which a normal subgroup $A$ acts trivially, we show that the $\alpha$-twisted $G$-equivariant $K$-theory of $X$ decomposes as…

Algebraic Topology · Mathematics 2021-04-22 José Manuel Gómez , Johana Ramírez

This article presents some computations for a new topological invariant for foliations introduced some years ago by the author using techniques from noncommutative geometry, in particular the pairing between K-Theory and cyclic cohomology.…

Mathematical Physics · Physics 2008-01-15 Ioannis P. Zois

We relate the Davis-L\"uck homology with coefficients in Weibel's homotopy K-theory to the equivariant algebraic kk-theory using homotopy theory and adjointness theorems. We express the left hand side of the assembly map for the…

K-Theory and Homology · Mathematics 2024-01-29 Eugenia Ellis , Emanuel Rodríguez Cirone