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Related papers: L^2-Betti numbers for subfactors

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For the $\bar\partial$-Neumann problem on a regular coordinate domain $\Omega\subset \C^{n+1}$, we prove $\epsilon$-subelliptic estimates for an index $\epsilon$ which is in some cases better than $\epsilon=\frac1{2m}$ ($m$ being the {\it…

Complex Variables · Mathematics 2009-01-07 Tran Vu Khanh , Giuseppe Zampieri

We investigate the values of the Riemann zeta function at odd integers and the Dirichlet beta function at even integers, by collecting several distinct analytic frameworks converging to these values, thus providing a unifying perspective.…

Number Theory · Mathematics 2026-01-26 Luc Ramsès Talla Waffo

In this paper we discuss open problems concerning L^2-invariants focusing on approximation by towers of finite coverings.

Geometric Topology · Mathematics 2016-10-07 Wolfgang Lueck

The number of Frattini chief factors or of chief factors which are complemented by a maximal subalgebra of a finite-dimensional Lie algebra $L$ is the same in every chief series for $L$, by \cite[Theorem 2.3]{[11]}. However, this is not the…

Rings and Algebras · Mathematics 2015-09-25 David A. Towers , Zekiye Ciloglu

In this paper, we look at quasiconformal solutions $\phi:\mathbb{C}\to\mathbb{C}$ of Beltrami equations $$ \partial_{\overline{z}} \phi(z)=\mu(z)\,\partial_z \phi (z). $$ where $\mu\in L^\infty(\mathbb{C})$ is compactly supported on…

Complex Variables · Mathematics 2015-07-22 Antonio Luis Baisón , Albert Clop , Joan Orobitg

The paper aims to investigate the classification problem of low dimensional complex none Lie filiform Leibniz algebras. There are two sources to get classification of filiform Leibniz algebras. The first of them is the naturally graded none…

Rings and Algebras · Mathematics 2007-10-02 I. S. Rakhimov , S. K. Said Husain

We interpret the construction of relative Cuntz-Pimsner algebras of correspondences in terms of the correspondence bicategory, as a reflector into a certain sub-bicategory. This generalises a previous characterisation of absolute…

Operator Algebras · Mathematics 2019-09-04 Ralf Meyer , Camila F. Sehnem

We present here a shorter version of the proof of a result from our paper ``On a class of type II$_1$ factors with Betti numbers invariants'', showing that the von Neumann factor associated with the group $\Bbb Z^2 \rtimes SL(2, \Bbb Z)$…

Operator Algebras · Mathematics 2007-05-23 Sorin Popa

We calculate all $\ell^2$-Betti numbers of the universal discrete Kac quantum groups $\hat U_n^+$ as well as their full half-liberated counterparts $\hat U_n^*$.

Operator Algebras · Mathematics 2017-06-14 Julien Bichon , David Kyed , Sven Raum

All subalgebras, idempotents, left(right) ideals and left quasi-units of two-dimensional algebras are described. Classification of algebras with given number of subalgebras, left(right) ideals are provided. In particular, a list of…

Rings and Algebras · Mathematics 2019-10-11 H. Ahmed , U. Bekbaev , I. Rakhimov

An $n$-dimensional Lie algebra $\mathfrak{g}$ over a field $\mathbb{F}$ of characteristic two is said to be of Vergne type if there is a basis $e_1,\dots,e_n$ such that $[e_1,e_i]=e_{i+1}$ for all $2\leq i \leq n-1$ and $[e_i,e_j] =…

Rings and Algebras · Mathematics 2015-11-11 Ioannis Tsartsaflis

This paper is to study vertex operator superalgebras which are strongly generated by their weight-$2$ and weight-$\frac{3}{2}$ homogeneous subspaces. Among the main results, it is proved that if such a vertex operator superalgebra $V$ is…

Quantum Algebra · Mathematics 2021-09-28 Haisheng Li , Nina Yu

The space of Lie algebra cohomology is usually described by the dimensions of components of certain degree even for the adjoint module as coefficients when the spaces of cochains and cohomology can be endowed with a Lie superalgebra…

K-Theory and Homology · Mathematics 2007-05-23 Alexei Lebedev , Dimitry Leites , Ilya Shereshevskii

In this paper, we consider Leibniz algebras with derivations. A pair consisting of a Leibniz algebra and a distinguished derivation is called a LeibDer pair. We define a cohomology theory for LeibDer pair with coefficients in a…

Rings and Algebras · Mathematics 2020-03-19 Apurba Das

In a paper by Lin an interesting family of semipermutations comes out to index the elements of a cohomology basis of a Hessenberg type variety. The corresponding Betti numbers are a generalization of Eulerian numbers. We show three…

Combinatorics · Mathematics 2026-01-27 Giovanni Gaiffi , Giovanni Interdonato

An alternative formula is presented for the evaluation of the zeta function values $\zeta(2k)$ without the need for Bernoulli numbers. Our formula is recursive, and improves the efficiency with which we can calculate large values of the…

Numerical Analysis · Mathematics 2011-11-18 Srinivasan Arunachalam

Suppose the ground field $\mathbb{F}$ is an algebraically closed field of characteristic different from 2, 3. We determine the Betti numbers and make a decomposition of the associative superalgebra of the cohomology for the model filiform…

Rings and Algebras · Mathematics 2018-11-05 Yong Yang , Wende Liu

Various generalizations of Cuntz algebras and their relations to symmetry and duality are reviewed. New generalized Cuntz algebras are associated with a subfactor. A characteristic Hilbert space of basic invariants (with respect to the…

funct-an · Mathematics 2008-02-03 K. -H. Rehren

We explain how the Harish-Chandra Plancherel Theorem and results in relative Lie algebra cohomology can be used in order to compute in a uniform way the $L^2$-Betti numbers, the Novikov-Shubin invariants, and the $L^2$-torsion of compact…

Differential Geometry · Mathematics 2007-05-23 Martin Olbrich

This paper introduces two new algorithms for Lie algebras over finite fields and applies them to the investigate the known simple Lie algebras of dimension at most $20$ over the field $\mathbb{F}_2$ with two elements. The first algorithm is…

Rings and Algebras · Mathematics 2023-06-22 Bettina Eick , Tobias Moede