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20112026
most citedThe universal property of inverse semigroup equivariant -theory

5 citations · 16 across the 16 of their papers we have counts for

collaborators

21 papers

math.KT2026

The universal property of graded -theory

Bernhard Burgstaller

To each Kasparov cycle we attach inclusions satisfying . A lift of a second factor along therefore re…

math.KT2025

Computing the -homology -theory product in splitexact algebraic -theory

Bernhard Burgstaller

Explicit formulas are indicated that compute the product of a level-one element and any element in splitexact algebraic…

math.KT2025

Corner embeddings into algebras of compact operators in -theory

Bernhard Burgstaller

We show that in -theory-like categories many corner embeddings into a discrete algebra of compact operators are invertible, and consequently functors on splitexact algebraic $KK…

math.KT2024

On the -theory in splitexact algebraic -theory

Bernhard Burgstaller

It is proven that in the universal splitexact equivariant algebraic -theory for algebras, the -theory groups coincide with classical -theory in the sense of Phillips. Thi…

cs.IT2022

Information content in formal languages

Bernhard Burgstaller

Motivated by creating physical theories, formal languages with variables are considered and a kind of distance between elements of the languages is defined by the formula $d(x,…

math.KT2021

A kind of -theory for rings

Bernhard Burgstaller

A group equivariant -theory for rings will be defined and studied in analogy to Kasparov's -theory for -algebras. It is a kind of linearization of the category of ring…

math.KT2019

Aspects of equivariant -theory in its generators and relations picture

Bernhard Burgstaller

We give a new proof of the universal property of -theory with respect to stability, homotopy invariance and split-exactness for a locally compact group, or a locally comp…

math.OA2019

Some remarks in - and -theory

Bernhard Burgstaller

This note consists of three unrelated remarks. First, we demonstrate how roughly speaking -homomorphisms between matrix stable -algebras are exactly the uniformly continuou…

math.OA2017

Semigroup homomorphisms on matrix algebras

Bernhard Burgstaller

We explore the connection between ring homomorphisms and semigroup homomorphisms on matrix algebras over rings or -algebras.

math.KT2016★ 2 cited

A note on a certain Baum--Connes map for inverse semigroups

Bernhard Burgstaller

Let denote a countable inverse semigroup. We construct a kind of a Baum--Connes map by a categorial approach via localization…

math.KT2016★ 3 cited

The generators and relations picture of -theory

Bernhard Burgstaller

This is half an overview article since what we describe here is essentially known. We describe -theory by generators and relations in a formal sum of formal products of -hom…

math.KT2015

Inverse semigroup equivariant -theory and -extensions

Bernhard Burgstaller

In this note we extend the classical result by G. G. Kasparov that the Kasparov groups can be identified with the extension groups $\mbox{Ext}(A,B)$ to the inverse semi…

math.KT2015★ 4 cited

Attempts to define a Baum--Connes map via localization of categories for inverse semigroups

Bernhard Burgstaller

Meyer and Nest showed that the Baum--Connes map is equivalent to a map on -theory of two different crossed products. This approach is strongly categorial in method since its bas…

math.OA2014★ 2 cited

A Green--Julg isomorphism for inverse semigroups

Bernhard Burgstaller

For every finite unital inverse semigroup and --algebra we establish an isomorphism between and . This extends the classical Gr…

math.OA2014

An elementary Green imprimitivity theorem for inverse semigroups

Bernhard Burgstaller

A Morita equivalence similar to that found by Green for crossed products by groups will be established for crossed products by inverse semigroups. More precisely, let be an inv…

math.OA2014★ 5 cited

The universal property of inverse semigroup equivariant -theory

Bernhard Burgstaller

Higson proved that every homotopy invariant, stable and split exact functor from the category of -algebras to an additive category factors through Kasparov's -theory. By a…

math.KT2012

Equivariant -theory of -discrete groupoids and inverse semigroups

Bernhard Burgstaller

For an -discrete Hausdorff groupoid and an inverse semigroup of slices of there is an isomorphism between -equivariant -theory and compat…

math.OA2011

On certain properties of Cuntz--Krieger type algebras

Bernhard Burgstaller

The note presents a further study of the class of Cuntz--Krieger type algebras. A necessary and sufficient condition is identified that ensures that the algebra is purely infinite,…

math.OA2011

A Cuntz--Krieger uniqueness theorem for semigraph -algebras

Bernhard Burgstaller

Higher rank semigraph algebras are introduced by mixing concepts of ultragraph algebras and higher rank graph algebras. This yields a kind of higher rank generalisation of ultragra…

math.OA2011

A descent homomorphism for semimultiplicative sets

Bernhard Burgstaller

We define and provide some basic analysis of various types of crossed products by semimultiplicative sets, and then prove a -theoretical descent homomorphisms for semimultiplic…

math.OA2011

On freely generated semigraph -algebras

Bernhard Burgstaller

For special universal -algebras associated to -semigraphs we present the universal representations of these algebras, prove a Cuntz--Krieger uniqueness theorem, and compute…