Die Dozenten der Informatik-Institute der Technischen Universität Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem Vortrag ein:

Prof. Dominique Bourn, Université du Littoral, Calais, Frankreich: Some aspects of intrinsic commutativity in Algebra

Beginn: 20.01.2005, 17:00 Uhr Ort: TU Braunschweig, Informatikzentrum, Mühlenpfordtstraße 23, 1. OG, Hörsaal M 161 Webseite: http://www.cs.tu-bs.de/kolloquium/bourn.htm

A pointed variety V is Jonsson-Tarski if its theory has a unique constant 0 and contains a binary operation + such that 0+x = x = x+0. It will be shown that a pointed variety V is Jonsson-Tarski if and only if, given any pair (X,Y) of algebras, and considering the diagram:

X --> X x Y <-- Y

the (sub)algebra X x Y is the supremum of the "subalgebras" X and Y. Thus, a classical Universal Algebra presentation is equivalent to a categorical presentation. The main aim of this talk is to compare or confront the different ways of defining commutativity in these equivalent contexts.