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Related papers: Bordisms and unbounded $KK$-theory

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A new class of noncommutative $k$-algebras (for $k$ an algebraically closed field) is defined and shown to contain some important examples of quantum groups. To each such algebra, a first order theory is assigned describing models of a…

Logic · Mathematics 2015-06-12 Vinesh Solanki

Given a connected manifold with corners of any codimension there is a very basic and computable homology theory called conormal homology defined in terms of faces and orientations of their conormal bundles, and whose cycles correspond…

K-Theory and Homology · Mathematics 2022-03-09 Paulo Carrillo Rouse , Jean-Marie Lescure , Mario Velasquez

We obtain a solution to a bordism version of Gromov's linearity problem over a large family of acyclic groups, for manifolds with arbitrary dimension. Every group embeds into some acyclic group in this family. Thus, the linear bordism…

Geometric Topology · Mathematics 2026-02-10 Jae Choon Cha , Geunho Lim

We consider the cobordism ring of involutions of a field of characteristic not two, whose elements are formal differences of classes of smooth projective varieties equipped with an involution, and relations arise from equivariant K-theory…

Algebraic Geometry · Mathematics 2021-08-10 Olivier Haution

By considering the general properties of approximate units in differentiable algebras, we are able to present a unified approach to characterising completeness of spectral metric spaces, existence of connections on modules, and the lifting…

Operator Algebras · Mathematics 2016-10-24 Bram Mesland , Adam Rennie

(Co)bordisms of manifolds and maps are fundamental and important objects in algebraic and differential topology of manifolds and related studies were started by Thom etc.. Cobordisms of Morse functions were introduced and have been studied…

Algebraic Topology · Mathematics 2019-03-19 Naoki Kitazawa

A group equivariant $KK$-theory for rings will be defined and studied in analogy to Kasparov's $KK$-theory for $C^*$-algebras. It is a kind of linearization of the category of rings by allowing addition of homomorphisms, imposing also…

K-Theory and Homology · Mathematics 2021-07-06 Bernhard Burgstaller

We define a sutured cobordism category of surfaces with boundary and 3-manifolds with corners. In this category a sutured 3-manifold is regarded as a morphism from the empty surface to itself. In the process we define a new class of…

Geometric Topology · Mathematics 2009-09-18 Rumen Zarev

This survey deals with the construction of a category of spectral triples that is compatible with the Kasparov product in $KK$-theory. These notes serve as an intuitive guide to these results, avoiding the necessary technical proofs. We…

K-Theory and Homology · Mathematics 2013-04-16 Bram Mesland

In this paper, we introduce Kasparov's bivariant K-theory that is equivariant under symmetries of a C*-tensor category. It is motivated by some dualities in quantum group equivariant KK-theory, and the classification theory of inclusions of…

Operator Algebras · Mathematics 2025-03-19 Yuki Arano , Kan Kitamura , Yosuke Kubota

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

When can a map between manifolds be deformed away from itself? We describe a (normal bordism) obstruction which is often computable and in general much stronger than the classical primary obstruction in cohomology. In particular, it answers…

Algebraic Topology · Mathematics 2007-05-23 Ulrich Koschorke

We introduce an equivariant Pontrjagin-Thom construction which identifies equivariant cohomotopy classes with certain fixed point bordism classes. This provides a concrete geometric model for equivariant cohomotopy which works for any…

Algebraic Topology · Mathematics 2018-11-22 Daniel Grady

The U-dualities of maximally supersymmetric supergravity theories lead to celebrated non-perturbative constraints on the structure of quantum gravity. They can also lead to the presence of global symmetries since manifolds equipped with…

High Energy Physics - Theory · Physics 2025-08-04 Noah Braeger , Arun Debray , Markus Dierigl , Jonathan J. Heckman , Miguel Montero

The outlines of a "Galois theory" for bimeromorphic geometry is here developed, via the study of model-theoretic definable binding groups in the theory CCM of compact complex spaces. As an application, a structure theorem about principal…

Logic · Mathematics 2025-12-15 Rahim Moosa , Anand Pillay

We adapt algorithms for resolving the singularities of complex algebraic varieties to prove that the natural map of homology theories from complex bordism to the bordism theory of complex derived orbifolds splits. In equivariant stable…

Algebraic Topology · Mathematics 2025-04-25 Mohammed Abouzaid , Shaoyun Bai

We construct spaces of 1-dimensional supersymmetric Euclidean field theories and show that they represent real or complex K-theory. A noteworthy feature of our bordism category is that the identity bordism of a point is connected to…

Algebraic Topology · Mathematics 2019-01-09 Peter Ulrickson

Noncommutative lattices have been recently used as finite topological approximations in quantum physical models. As a first step in the construction of bundles and characteristic classes over such noncommutative spaces, we shall study their…

q-alg · Mathematics 2008-02-03 Elisa Ercolessi , Giovanni Landi , Paulo Teotonio-Sobrinho

In this paper, we define a relative $L^2$-$\rho$-invariant for Dirac operators on odd-dimensional spin manifolds with boundary and show that they are invariants of the bordism classes of positive scalar curvature metrics which are collared…

Geometric Topology · Mathematics 2020-09-30 Simone Cecchini , Mehran Seyedhosseini , Vito Felice Zenobi

Quantization, at least in some formulations, involves replacing some algebra of observables by a (more non-commutative) deformed algebra. In view of the fundamental role played by K-theory in non-commutative geometry and topology, it is of…

q-alg · Mathematics 2013-02-28 Jonathan Rosenberg