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15:11
It might be a dumb question but in a closed monoid category, shall we have a 'forgetful functor' sort of thing, from internal hom to the set of morphism? Or is it a part of definition?
yeah, you can take the "underlying set" of an object X of C to be the set of maps from the unit to X
it works pretty well if C is closed monoidal
Thank you! It seems that I am really dumb.
 
2 hours later…
17:02
@Mingcong: but note that unlike most "forgetful functors" there's no reason Hom(1, X) should be faithful; in other words, in general it forgets more than "structure," it forgets "stuff"
17:18
Yeah I realized that. It has no reason to make our category concrete.
17:35
At least you get back what you started with in this case.
 
5 hours later…
22:48
Given an algebraic group G and a principal G bundle X-->Y, there's a map Y-->BG (in schemes?) classifying this, right?
Or do we have to pass to stacks or something?
I don't think BG is going to be a scheme...
23:25
@Jon: BG is a stack
23:36
Yeah. OK cool. That's what I thought. Thanks!
23:58
Interested beginners in algebraic topology should definitely try to get to the UChicago Summer school in Algebraic Topology this year: math.uchicago.edu/~chicagotopology2

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