English
Related papers

Related papers: A generalization of the topological Brauer group

200 papers

In this note we introduce the notion of bundle gerbe K-theory and investigate the relation to twisted K-theory. We provide some examples. Possible applications of bundle gerbe K-theory to the classification of D-brane charges in non-trivial…

High Energy Physics - Theory · Physics 2008-11-26 P. Bouwknegt , A. L. Carey , V. Mathai , M. K. Murray , D. Stevenson

Our main theorem is that the inclusion of a Birkhoff variety in the affine Grassmannian is a homotopy equivalence. We also construct analogues of tubular neighborhoods for Birkhoff and Schubert varieties. We include some observations on…

Algebraic Topology · Mathematics 2009-03-30 Luke Gutzwiller , Stephen A. Mitchell

We define inductively a sequence of purely algebraic invariants - namely, classes in the Quillen cohomology of the Pi-algebra \pi_* X - for distinguishing between different homotopy types of spaces. Another sequence of such cohomology…

Algebraic Topology · Mathematics 2009-10-31 David Blanc

In this paper, we study a generalization of twisted (groupoid) equivariant $\mathrm{K}$-theory in the sense of Freed-Moore for $\mathbb{Z}_2$-graded $\mathrm{C}^*$-algebras. It is defined by using Fredholm operators on Hilbert modules with…

K-Theory and Homology · Mathematics 2016-02-10 Yosuke Kubota

Representing Z/N as roots of unity, we restrict a natural U(1)-action on the Heegaard quantum sphere to Z/N, and call the quotient spaces Heegaard quantum lens spaces. Then we use this representation of Z/N to construct an associated…

K-Theory and Homology · Mathematics 2011-10-27 Piotr M. Hajac , Adam Rennie , Bartosz Zielinski

The classifying space of the embedded cobordism category has been identified in by Galatius, Tillmann, Madsen, and Weiss as the infinite loop space of a certain Thom spectrum. This identifies the set of path components with the classical…

Algebraic Topology · Mathematics 2016-02-24 Marcel Bökstedt , Anne Marie Svane

We first apply the method and results in the previous paper to give a new proof of a result (hold in $ {\bf C}/{\bf Z}$) of Gilkey on the variation of h-invariants associated to non self-adjoint Dirac type operators. We then give an…

Differential Geometry · Mathematics 2007-05-23 Xiaonan Ma , Weiping Zhang

We discuss some bulk-surfaces gapped Hamiltonians on a lattice with corners and propose a periodic table for topological invariants related to corner states aimed at studies of higher-order topological insulators. Our table is based on four…

Mathematical Physics · Physics 2021-09-29 Shin Hayashi

For a continuous field of the Cuntz algebra over a finite CW complex, we introduce a topological invariant, which is an element in Dadarlat-Pennig's generalized cohomology group, and prove that the invariant is trivial if and only if the…

Operator Algebras · Mathematics 2020-02-18 Taro Sogabe

The aim of section 1 is to define the homotopic functor to category of Abelian groups, connected with the special classes of bundles with fiber matrix algebra or projective space. The aim of section 2 is to define some generalization of the…

Algebraic Topology · Mathematics 2007-05-23 A. V. Ershov

We establish a relative version of the abstract "affine representability" theorem in ${\mathbb A}^1$--homotopy theory from Part I of this paper. We then prove some ${\mathbb A}^1$--invariance statements for generically trivial torsors under…

Algebraic Geometry · Mathematics 2018-03-16 Aravind Asok , Marc Hoyois , Matthias Wendt

Let $G$ be the identity component of the isometry group for an arbitrary curved two-point homogeneous space $M$. We consider algebras of $G$-invariant differential operators on bundles of unit spheres over $M$. The generators of this…

Representation Theory · Mathematics 2009-11-07 Alexey V. Shchepetilov

We study the category of wheeled PROPs using tools from Invariant Theory. A typical example of a wheeled PROP is the mixed tensor algebra ${\mathcal V}=T(V)\otimes T(V^\star)$, where $T(V)$ is the tensor algebra on an $n$-dimensional vector…

Representation Theory · Mathematics 2019-09-04 Harm Derksen , Visu Makam

We investigate invertible elements and gradings in braided tensor categories. This leads us to the definition of theta-, product-, subgrading and orbitcategories in order to construct new families of BTC's from given ones. We use the…

High Energy Physics - Theory · Physics 2008-02-03 Thomas Kerler

The paper is the survey of the modern results and applications of the theory of homotopes. The notion of a well-tempered element in an associative algebra is introduced and it is proven that the category of representations of the homotope…

Representation Theory · Mathematics 2021-08-11 Alexey Bondal , Ilya Zhdanovskiy

Implementing an idea due to John Baez and James Dolan we define new invariants of Whitney stratified manifolds by considering the homotopy theory of smooth transversal maps. To each Whitney stratified manifold we assign transversal homotopy…

Algebraic Topology · Mathematics 2009-10-20 Jonathan Woolf

We prove a version of Quillen's stratification theorem in equivariant homotopy theory for a finite group $G$, generalizing the classical theorem in two directions. Firstly, we work with arbitrary commutative equivariant ring spectra as…

Algebraic Topology · Mathematics 2024-11-26 Tobias Barthel , Natalia Castellana , Drew Heard , Niko Naumann , Luca Pol

We construct a covariant functor from the topological torus bundles to the so-called Cuntz-Krieger algebras; the functor maps homeomorphic bundles into the stably isomorphic Cuntz-Krieger algebras. It is shown, that the K-theory of the…

Operator Algebras · Mathematics 2011-02-21 Igor Nikolaev

The concept of Rota-Baxter family algebra is a generalization of Rota-Baxter algebra. It appears naturally in the algebraic aspects of renormalizations in quantum field theory. Rota-Baxter family algebras are closely related to dendriform…

Rings and Algebras · Mathematics 2023-01-02 Apurba Das

We present a method for computing $\mathbb{A}^1$-homotopy invariants of singularity categories of rings admitting suitable gradings. Using this we describe any such invariant, e.g. homotopy K-theory, for the stable categories of…

K-Theory and Homology · Mathematics 2020-05-19 Sira Gratz , Greg Stevenson