4 Dec
2016
4 Dec
'16
noon
Steve, we are speaking about different things. Pullbacks of bgm's along arbitrary gm's are described sufficiently well [Joh77] and in the Elephant. But what I have commented on was how to appropriately captured change of base when studying topose sover a base topos. I am working on the "algebraic" side whereas you think on the "geometric" side. Reindexing in terms of the algebraic view is given by precomposition but reindexing in terms of the geometric view is postcomposition. What I want to say is that pullbacks in Top are very different from the change of base for relative topos theory. Thomas [For admin and other information see: http://www.mta.ca/~cat-dist/ ]