4,206 reputation
21747
bio website bruno.stonek.com
location Montevideo, Uruguay
age 25
visits member for 3 years, 11 months
seen 1 hour ago

Math student at Université Paris 13.


Sep
8
answered History of category theory
Aug
31
awarded  Favorite Question
Jul
21
awarded  Good Question
Jul
17
awarded  Favorite Question
Jul
2
awarded  Curious
Jul
2
awarded  Inquisitive
Jun
20
comment On pushouts and mapping cylinders in exact categories
For the prospective reader, I might add that the easy observation that the forgetful functor from $C\mathcal N$ to the category of graded objects over $\mathcal N$ reflects exactness is implicitly being used.
Jun
17
comment On pushouts and mapping cylinders in exact categories
Great! In fact, not too many days ago I managed to solve the problem with help from my supervisor, and I was planning to post it here very soon. I got the same thing as you though I had to use elements to be convinced that the $P$ you define is effectively the pushout, etc. Thanks a lot for your effort on an already old and quite ignored question.
Jun
17
accepted On pushouts and mapping cylinders in exact categories
Jun
9
accepted Is $\Omega \tilde X \simeq \Omega_0 X$?
May
30
comment Is $\Omega \tilde X \simeq \Omega_0 X$?
Thanks! I'll eagerly read your expanded answer.
May
30
comment Is $\Omega \tilde X \simeq \Omega_0 X$?
Nice! I really like the argument, very clean. Didn't Milnor prove a theorem that loop spaces of CW-complexes have the homotopy type of a CW complex? (I didn't really ever read the actual formal statement), if that's the case then if $X$ is a CW-complex the proof works, and I'm interested in CW complexes so that's that :)
May
30
comment Is $\Omega \tilde X \simeq \Omega_0 X$?
Well ok, this is essentially the statement of the unique path lifting property, disregarding continuity issues, I think. What I still don't really get is why $\Omega_0$ appears.
May
30
asked Is $\Omega \tilde X \simeq \Omega_0 X$?
May
21
awarded  Famous Question
May
21
comment showing exact functors preserve exact sequences (abelian categories, additive functors, and kernels)
+1. This old answer of mine comes to mind.
May
16
comment Equivalent conditions for a preabelian category to be abelian
@t.b.: Almost three years later, I got to the point where I need to get into exact categories (as I seem to be getting into algebraic K-theory...) and your article seems to be the current standard reference. And it is a joy to read, your exposition is wonderful! It's sad that you don't hang around here anymore... Perhaps you will see this comment, and perhaps by the time you see it this question which shouts your name will have been answered already.
May
16
comment On pushouts and mapping cylinders in exact categories
Oh, I wish @t.b. wasn't "on extended leave" from the site...
May
16
asked On pushouts and mapping cylinders in exact categories
May
14
comment What should a student (with algebraic-geometry minded) study in differential geometry?
Isn't just studying differential geometry good enough for every purpose? Just a thought.