Supergeometric theories and set-generated classes

Mercoledi' 5 Ottobre 2011 - Hajime Ishihara


Mercoledi' 5 Ottobre 2011, alle ore 11:30 in aula 1BC45, il prof. Hajime Ishihara (JAIST, Giappone) terra' un seminario dal titolo "Supergeometric theories and set-generated classes".

We introduce supergeometric theories over a set S and their models which are subsets of S. Then we show that the class M of models of a supergeometric theory is set-generated in CZF, that is, there exists a subset G of M such that each set a in M is the union of subsets of a in G. We also present some applications to formal topology and Sambin's theory of basic pairs.

Rif. int. M.E. Maietti