David Roberts saturated pretopology

A saturated singleton pretopology is a singleton pretopology JJ such that if the composite xyzx\to y \to z is in JJ, then yzy \to z is in JJ.

The canonical example is the class of maps admitting local sections for a given pretopology on a category with pullbacks.

Created on April 1, 2009 at 05:39:06. See the history of this page for a list of all contributions to it.