Triquotient maps versus ultrafilter convergence
by
Maria Manuel Clementino
Department of Mathematics, University of Coimbra
Coauthors: Dirk Hofmann (University of Coimbra)

In the realm of finite spaces, Janelidze and Sobral [2] gave interesting characterizations of universal quotient, effective descent and triquotient maps (see also [1]).

In this talk we present a characterization of triquotient maps, that generalizes the previous one, combining ultrafilters convergence. This gives rise to the study of the category of ultrarelational spaces, that contains as full subcategories Top and PsTop.

[1] M.M. Clementino, " On finite triquotient maps", Preprint 00-15, Department of Mathematics, University of Coimbra, 2000.

[2] G. Janelidze and M. Sobral, "Finite preorders and topological descent", Preprint 99-10, Department of Mathematics, University of Coimbra, 1999.

Date received: May 31, 2000

Copyright © 2000 by the author(s). The author(s) of this document and the organizers of the conference have granted their consent to include this abstract in Atlas Conferences Inc. Document # caeq-29.