bio  website  math.berkeley.edu/~qchu 

location  Berkeley, CA  
age  23  
visits  member for  4 years, 6 months 
seen  3 hours ago  
stats  profile views  47,893 
I'm a secondyear graduate student in pure mathematics at UC Berkeley. You can contact me at qchu[at]math[dot]berkeley[dot]edu.
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What is ChernSimons theory expected to assign to a point?
For anyone else thinking of watching the video, Youtube has 1.5x and 2x speed options, and I promise that the video is still understandable at those speeds! 
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accepted  What is ChernSimons theory expected to assign to a point? 
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Generating function which has no singularity
You can use e.g. the saddlepoint method. See in particular Example VIII.3 of Flajolet and Sedgewick. 
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What is ChernSimons theory expected to assign to a point?
@André: thanks for the response! I worry that I asked you this question in person already and forgot your answer, so I'm glad it's now recorded electronically. I'll try to find some time to watch the video. 
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answered  is the tensor product of projective modules again projective? 
2d

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The AlexanderConway polynomial: from knots to braids?
This is not the question you want to ask. Closing up a braid to a knot should be thought of as a trace, so what you really want is a map from braids to matrices with polynomial coefficients (probably a representation of the braid group) such that taking traces gives back the Alexander polynomial (this is exactly what happens for the Jones polynomial, where the corresponding representation is built using e.g. quantum groups). Maybe the Burau representation is such a representation? 
Apr 14 
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What is ChernSimons theory expected to assign to a point?
@Adrien: I'm willing to believe you can't go down to the point with the target $3$category I described above, but that doesn't preclude the possibility of switching to a more sophisticated target $3$category, right? I also admit that I don't understand this anomaly issue at all; going to have to read more about that. 
Apr 14 
awarded  Nice Question 
Apr 14 
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Gspaces and manifolds
What a confusing term. A $G$space should be a space equipped with an action of $G$... 
Apr 14 
revised 
What is ChernSimons theory expected to assign to a point?
added 26 characters in body 
Apr 14 
asked  What is ChernSimons theory expected to assign to a point? 
Apr 12 
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EilenbergMacLane Spaces of “large” groups
I think "infinite and discrete and not $\mathbb{Z}$" is too broad for the question you actually want to ask. There are lots of reasonable $K(G, 1)$ in this category, e.g. aspherical manifolds. Maybe uncountable $G$? 
Apr 11 
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Squarefree integers not divisible by any “small” primes
Some very rough heuristics suggest a constant times $\frac{kN}{\log N}$; see qchu.wordpress.com/2012/11/10/… for a rough description of those heuristics. 
Apr 10 
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Algebraic topology vs. category theory
The morphisms are homotopy classes of functions. The resulting category is called the homotopy category of spaces. This is standard material. 
Apr 8 
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Characters and conjugacy classes
For infinite groups there are examples of groups that have no finitedimensional representations whatsoever (e.g. simple groups of cardinality strictly larger than the continuum). 
Apr 7 
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What is an intuitive view of adjoints? (version 1: category theory)
Actually, it's the other way around: the left adjoint is the ceiling and the right adjoint is the floor. If $r \in \mathbb{R}$ and $n \in \mathbb{Z}$ then $\lceil r \rceil \le n$ if and only if $r \le n$, and dually $n \le \lfloor r \rfloor$ if and only if $n \le r$. 
Apr 4 
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When a symplectic manifold is formal?
@user: perhaps the OP is using the symplectic form to identify forms and polyvector fields, then using the Schouten bracket? 
Apr 4 
awarded  Nice Question 
Apr 2 
awarded  Great Answer 
Apr 2 
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Split exact categories arising naturally
Do you consider it natural to consider finitely generated projective modules over an arbitrary $\text{Ab}$enriched category? These shouldn't be equivalent to a category of modules over a ring if the category you start with has infinitely many objects. ("Finitely generated" means "admits an epimorphism from a finite coproduct of representables." Projective has the same meaning as usual.) 