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bio website math.berkeley.edu/~qchu
location Berkeley, CA
age 24
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I am a third-year graduate student at UC Berkeley. I'm interested in the interplay between homotopy theory, quantum field theory, manifold topology, and higher category theory.


20h
answered Simply connected Lie groups homeomorphic to R^n are solvable
1d
answered Has any attempt been made to classify finite groupoids?
2d
comment When does the Borel construction have the homotopy type of a CW-complex?
Presumably this depends on a choice of $EG$. What $EG$ are you choosing?
2d
awarded  Nice Answer
2d
awarded  Necromancer
2d
revised UFD and fundamental group
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2d
comment Stiefel-Whitney class of complex projective spaces
Crossposted: math.stackexchange.com/questions/1206867/…
2d
answered UFD and fundamental group
Mar
25
comment Moduli space of flat connections over a torus
It is not a manifold in general. Lots of stuff is known about these sorts of spaces; one keyword you can use is "character variety."
Mar
25
revised Generators of invariant polynomials of semisimple Lie algebra
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Mar
25
comment Moduli space of flat connections over a torus
What do you mean by "known"? The moduli space of flat $G$-connections on a torus is the space $\{ (g, h) \in G^2 : gh = hg \}$ of commuting pairs of elements of $G$ ($g, h$ are given by monodromy around a pair of generators of $\pi_1$) modulo the action of $G$ given by simultaneous conjugation. What does it mean to know this space?
Mar
25
answered What is an infinite prime in algebraic topology?
Mar
25
revised Generators of invariant polynomials of semisimple Lie algebra
deleted 1 character in body
Mar
25
answered Generators of invariant polynomials of semisimple Lie algebra
Mar
25
comment Galois cohomology out of the classifying stack
Cohomology of a stack is contravariant in the stack, but Galois cohomology is covariant in $G$.
Mar
25
comment Generators of invariant polynomials of semisimple Lie algebra
@David: that's a basis of symmetric functions as a vector space, not a choice of generators as an algebra.
Mar
23
comment Are there any natural differential operators besides $d$?
@David: I haven't thought very hard about this, but can't you do things like consider an extension of $d$ to symmetric powers of $1$-forms?
Mar
22
comment Are there any natural differential operators besides $d$?
@Daniel: the Lie derivative and contractions are natural with respect to diffeomorphisms, but they are not natural with respect to arbitrary smooth maps (since vector fields can't be transported along arbitrary smooth maps).
Mar
22
comment Are there any natural differential operators besides $d$?
Natural Operations in Differential Geometry is dedicated to answering questions of this form: emis.de/monographs/KSM/kmsbookh.pdf
Mar
21
answered Isomorphism of various gauge groups under homotopy