5 Jun
1992
5 Jun
'92
6 p.m.
Date: Tue, 02 Jun 92 21:20:34 ADT From: dbenson@yoda.eecs.wsu.edu (David B. Benson)
Given a pair of arrows with common codomain, the pullback consists of an object and a pair of pullback projections with the requisite universal properties. Now for the question:
Regular is to equalizer as X is to pullback projections.
What name for a pair of arrows with a common domain should replace X in the above line?
Thanks, David
X = "pullback span" (see March 1972 thesis of Jeanne Meisen supervised by Jim Lambek at McGill) or, in the additive case, X = "relation" (see Peter Hilton's LaJolla paper, 1965). Regards, Ross ==========================================================================