Ganna Kudryavtseva in Primož Škraba: Filtered functors and internal actions related to inverse semigroups

Datum objave: 2. 3. 2015
Seminar za temelje matematike in teoretično računalništvo
Torek, 3. marec 2014, od 12h do 14h, Plemljev seminar, Jadranska 19
Abstract: This talk is a contribution to the development of the theory of internal actions of inverse semigroups in toposes. We prove that the category of filtered functors from the Loganathan’s category L(S) of an inverse semigroup S to the topos of sheaves Sh(X) on a topological space X is equivalent to the category of universal representations of S in Sh(X). This upgrades to Sh(X) the result proved by Funk and Hofstra for the topos of sets. For the topos of sets, we show that torsion-free functors on L(S) are equivalent to a special class of non-strict representations of S, which we call connected, whereas the latter representations form a proper coreflective subcategory of the category of all non-strict representations of S.