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bio website math.northwestern.edu/…
location Seattle, WA
age 22
visits member for 4 years, 5 months
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Graduate student at Northwestern. Feel free to email me at dwilson [at] u. northwestern. edu :)

6h
comment Functoriality of the adjoint functor construction?
It seems like what you're asking is the following: "Suppose I have a cartesian fibration which is locally cocartesian, is it also cocartesian?" The answer to that question is "yes", but I may be misunderstanding your question.
Nov
8
comment Role of determinant of the matrix corresponding to $i$-th Homology group.
For (1): The trace of the matrix associated to a permutation of the basis of your vector space is precisely the number of fixed points of the permutation. For (2): Don't have much but, if you have a self-map of a torus T^n then the determinant of the map on H^1 is the map on H^n.
Oct
19
comment Do the algebras for a $\infty$-monad form a stable $\infty$-category?
On the other hand, maybe the OPs assumptions on $T$ will force the forgetful functor to preserve finite coproducts... since the forgetful functor preserves sifted colimits, this should give you the preservation of colimits that you're after. (If it works it will probably work under the weaker assumption that $T$ preserves coproducts.)
Oct
19
comment Do the algebras for a $\infty$-monad form a stable $\infty$-category?
Alg_T(C) is certainly not equivalent to its image in C! The maps are not the same.
Oct
11
answered Steenrod operations in algebraic geometry
Oct
10
awarded  Popular Question
Oct
9
comment Number of minimal models of a surface
In this case the minimal model is determined by a rank 2 vector bundle on a curve of genus $H^1(\mathcal{O}_X)$, up to possible twist by a line bundle. I don't know off-hand how large this is... I believe for elliptic curves there's only countably many such things (see Atiyah's paper on the subject).
Sep
19
comment Letter from Grothendieck to Tate on “crystals”
although it looks like the top of every page is missing a line... which is unfortunate.
Sep
19
comment Letter from Grothendieck to Tate on “crystals”
weird... it works now. Maybe I had a bad internet connection, or the site was having trouble earlier. Thank you!
Sep
18
comment Letter from Grothendieck to Tate on “crystals”
Did you ever end up writing up the letter? The link in your post doesn't seem to be working, and I can't find the letter elsewhere by googling.
Sep
5
comment $H^4(BG,\mathbb Z)$ torsion free for $G$ a connected Lie group
but that's perhaps just as computational, and only covers the simply-connected case.
Sep
5
comment $H^4(BG,\mathbb Z)$ torsion free for $G$ a connected Lie group
If $G$ is simply connected then $\pi_i(G)$ is torsion-free for $i<4$ since $\pi_2$ of a Lie group is zero and $\pi_3$ is always torsion-free. Thus $\pi_i(BG)$ is torsion-free for $i\le 4$ and the result follows from mod C Hurewicz.
Aug
23
comment Morava $K(n)$'s are not $E_{\infty}$
At the prime 2 I don't even think they're homotopy commutative. In general they're probably not more than like... E_2. I don't know a reference... maybe Ravenel's orange book?
Jul
15
awarded  Informed
Jul
4
comment Mapping complexes in the simplicial localization of the category of manifolds
Oh dear you're right! My argument didn't make any sense- I think I was assuming something absolutely absurd in my head... like that $Mfld[W^{-1}]$ is a full subcategory of $Mfld$. hehe. doy...
Jul
4
revised Mapping complexes in the simplicial localization of the category of manifolds
added 137 characters in body
Jul
4
answered Mapping complexes in the simplicial localization of the category of manifolds
Jul
2
awarded  Curious
Jun
23
awarded  Great Question
Jun
23
awarded  Famous Question