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bio website math.northwestern.edu/…
location Seattle, WA
age 22
visits member for 4 years, 9 months
seen 20 hours ago
Graduate student at Northwestern. Feel free to email me at dwilson [at] u. northwestern. edu :)

Mar
15
comment Brandt's definition of groupoids (1926)
is one of your "groupoids" supposed to say "categories"?
Mar
10
comment How to prove that any perfect complex on an affine scheme is strictly perfect?
(and the reference for my entire comment, almost verbatim, is Thomason's classification of triangulated subcategories paper)
Mar
10
comment How to prove that any perfect complex on an affine scheme is strictly perfect?
Here's something that is true: On any scheme with an ample family of line bundles (e.g. quasi-projective, or affine, or separated regular Noetherian) every perfect complex is quasi-isomorphic to a strictly perfect complex. I'm not sure if that's what you meant by "is" in your claim, but the reference is SGA6 II.2.2.8 or Thomason-Trobaugh 2.3.1.
Mar
7
comment Lemma 2.1.1.4 in Lurie's HTT
For the first question: I believe the exact thing I need is the aforementioned corollary or 2.1.2.10, I can try to rewrite this more clearly later.
Mar
7
comment Lemma 2.1.1.4 in Lurie's HTT
For your second question: Applying the last argument for $Y = K$ and $Y = X_s$ shows that in both cases the homotopy class of a lift is determined by $f$, i.e. there is only one homotopy class of lift for $K \times \Delta^1 \rightarrow S$ so it must be the one obtained by composiiton.
Mar
7
comment Lemma 2.1.1.4 in Lurie's HTT
(Alternatively I can quote Corollary 2.1.2.9 of HTT if you don't like that argument at the end.)
Mar
7
answered Lemma 2.1.1.4 in Lurie's HTT
Feb
10
comment Anything between vector bundles and sphere bundles?
I thing taking connective covers moves the wrong way. For example, we have a map $BO \rightarrow BhAut(S)$. What you're trying to do (stably) is factor this map through other things. A connective cover, say $SO$, gives a map $BSO \rightarrow BO$ which is not what you want.
Feb
9
awarded  Popular Question
Feb
8
awarded  Nice Question
Feb
8
accepted Mazur secret Bourbaki report “Analyse p-adique”
Feb
8
comment Mazur secret Bourbaki report “Analyse p-adique”
This is awesome! Thanks for your heroic dedication to the spread of knowledge! Hope the physicists didn't burn down your office though...
Feb
8
awarded  Inquisitive
Feb
7
comment Mazur secret Bourbaki report “Analyse p-adique”
Apparently it's been too long since I've asked a question and I've forgotten where to find the "Community Wiki" option... Help?
Feb
7
asked Mazur secret Bourbaki report “Analyse p-adique”
Jan
20
comment What is modular representation theory for groups good for?
Quillen used some of this stuff, and needed various facts about $H^*(GL_n(\mathbb{F}_p), \mathbb{Z}/p)$ to prove the Adams conjecture and compute the algebraic K theory of finite fields.
Dec
17
awarded  Good Question
Dec
11
awarded  Nice Answer
Dec
11
revised Obstructions for $E_n$-algebras
added 74 characters in body
Dec
11
comment Obstructions for $E_n$-algebras
@SeanTilson You're absolutely right, of course, they start with a commutative comodule. The Dyer-Lashof operations then appear in computing the obstructions- in fact, all of the computations take place in the category of algebras in simplicial comodules over a certain simplicial operad. I'll amend the answer accordingly.