In Joyal-Nielsen-Winskel (p.13) is given the following definition. For what a “path category in a category of models” is, see there.


Let PP be a path category in a category of models MM. Two objects X 1,X 2X_1,X_2 are called to be PP-bisimilar if there is a span of PP-open maps X 1XX 2X_1\leftarrow X\to X_2.

The relation of PP-open maps and open maps is given by Proposition 11, p.32:


If PP is a dense full subcategory of MM, then ff-is PP-open iff M(,f)M(-,f) is an open map.

Last revised on March 19, 2014 at 06:52:48. See the history of this page for a list of all contributions to it.