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Related papers: Twisted $L^2$-Betti numbers of sofic groups

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We count the number of isomorphism classes of degree $d$-twists of some polarized abelian varieties over finite fields of odd prime dimension. This can be seen as a higher dimensional analogue of the counting problem for elliptic curves…

Number Theory · Mathematics 2020-06-16 WonTae Hwang , Keunyoung Jeong

Given a saturated Fell bundle A over an inverse semigroup S which is semi-abelian in the sense that the fibers over the idempotents of S are commutative, we construct a twisted etale groupoid L such that A can be recovered from L in a…

Operator Algebras · Mathematics 2009-08-30 Alcides Buss , Ruy Exel

We show that given a Frobenius algebra there is a unique notion of its second quantization, which is the sum over all symmetric group quotients of n--th tensor powers, where the quotients are given by symmetric group twisted Frobenius…

Algebraic Geometry · Mathematics 2009-11-07 Ralph M. Kaufmann

Vanishing results for reduced $L_{p,q}$-cohomology are established in the case of twisted products, which are a~generalization of warped products. Only the case $q \leq p$ is considered. This is an extension of some results by Gol'dshtein,…

Geometric Topology · Mathematics 2015-09-29 Vladimir Gol'dshtein , Yaroslav Kopylov

A twisting system is one of the major tools to study graded algebras, however, it is often difficult to construct a (non-algebraic) twisting system if a graded algebra is given by generators and relations. In this paper, we show that a…

Rings and Algebras · Mathematics 2022-05-03 Masaki Matsuno

Let $\overline{M}$ be a compact smoothly stratified pseudo-manifold endowed with a wedge metric $g$. Let $\overline{M}_\Gamma$ be a Galois $\Gamma$-covering. Under additional assumptions on $\overline{M}$, satisfied for example by Witt…

Differential Geometry · Mathematics 2024-09-12 Francesco Bei , Paolo Piazza , Boris Vertman

An odd generalized metric E_{-} on a Lie group G of dimension n is a left-invariant generalized metric on a Courant algebroid E_{H, F} of type B_n over G with left-invariant twisting forms H and F. Given an odd generalized metric E_{-} on G…

Differential Geometry · Mathematics 2023-11-02 Vicente Cortés , Liana David

Four-dimensional twisted group lattices are used as models for space-time structure. Compared to other attempts at space-time deformation, they have two main advantages: They have a physical interpretation and there is no difficulty in…

High Energy Physics - Theory · Physics 2009-10-28 O. Lechtenfeld , S. Samuel

We prove a Kunneth formula computing the Connes-Shlyakhtenko L^2-Betti numbers of the algebraic tensor product of two tracial *-algebras in terms of the L^2-Betti numbers of the two original algebras. As an application, we construct…

Operator Algebras · Mathematics 2009-03-06 David Kyed

Twisted \'etale groupoid algebras have been studied recently in the algebraic setting by several authors in connection with an abstract theory of Cartan pairs of rings. In this paper, we show that extensions of ample groupoids correspond in…

Rings and Algebras · Mathematics 2021-01-26 Benjamin Steinberg

We survey results related to the magnitude of the Betti numbers of numerical semigroup rings and of their tangent cones.

Commutative Algebra · Mathematics 2020-08-05 Dumitru I. Stamate

Two Seifert surfaces of links in $S^3$ are said to be twist equivalent if one can be obtained from the other, up to isotopy, by repeatedly performing operations consisting of cutting along an embedded arc, applying a full twist near one…

Geometric Topology · Mathematics 2016-04-08 Carson Rogers

The shifting numbers measure the asymptotic amount by which an endofunctor of a triangulated category translates inside the category, and are analogous to Poincare translation numbers that are widely used in dynamical systems. Motivated by…

Dynamical Systems · Mathematics 2023-07-21 Yu-Wei Fan

We show that the baryon number of N=2 supersymmetric QCD can be twisted in order to couple the topological field theory of non-abelian monopoles to $Spin^c$-structures. To motivate the construction, we also consider some aspects of the…

High Energy Physics - Theory · Physics 2009-10-30 J. M. F. Labastida , M. Marino

We introduce a twisted version of the Heisenberg double, constructed from a twisted Hopf algebra and a twisted Hopf pairing. We state a Stone--von Neumann type theorem for a natural Fock space representation of this twisted Heisenberg…

Quantum Algebra · Mathematics 2016-04-08 Daniele Rosso , Alistair Savage

We show that every groupoid C*-algebra is isomorphic to its opposite, and deduce that there exist C*-algebras that are not stably isomorphic to groupoid C*-algebras, though many of them are stably isomorphic to twisted groupoid C*-algebras.…

Operator Algebras · Mathematics 2017-08-15 Alcides Buss , Aidan Sims

Using general principles of the theory of vertex operator algebras and their twisted modules, we obtain a bosonic, twisted construction of a certain central extension of a Lie algebra of differential operators on the circle, for an…

Quantum Algebra · Mathematics 2007-05-23 Benjamin Doyon , James Lepowsky , Antun Milas

Drinfeld twists, and the twists of Giaquinto and Zhang, allow for algebras and their modules to be deformed by a cocycle. We prove general results about cocycle twists of algebra factorisations and induced representations and apply them to…

Quantum Algebra · Mathematics 2025-01-14 Yuri Bazlov , Edward Jones-Healey

We study $\ell^2$ Betti numbers, coherence, and virtual fibring of random groups in the few-relator model. In particular, random groups with negative Euler characteristic are coherent, have $\ell^2$ homology concentrated in dimension 1, and…

Group Theory · Mathematics 2022-06-15 Dawid Kielak , Robert Kropholler , Gareth Wilkes

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