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bio website math.berkeley.edu/~ianagol
location Berkeley
age 43
visits member for 4 years, 5 months
seen 9 hours ago

I'm a professor at UC Berkeley working predominantly in the field of low-dimensional topology.


10h
comment Cohomological Proof of Serre Relations for a Symmetrizable Kac-Moody Algebra
You might check out Lectures 26 and 27 in these notes: stacky.net/files/written/LieGroups/LieGroups.pdf These are lectures of Borcherds, who bases the construction of $E_8$ on constructions of Kac-Moody algebras from vertex algebras. So this might be a good warm-up.
1d
answered Embedding a linearly ordered free monoid into a linearly ordered group
2d
revised Can finitely generated subgroups of limit groups be detected in free group quotients?
added 534 characters in body
2d
answered Can finitely generated subgroups of limit groups be detected in free group quotients?
Apr
15
comment Algorithms in hyperbolic groups
I'm interested in implementation of algorithms, but don't have the computational skills to carry them out. Luckily, there are some people who can. I think the issue may be embedded in academia: if a mathematician spends their time implementing algorithms, then are they doing "math research", or are they just computer programming? I think there should be recognized a certain class of mathematician, "experimental mathematician", that explores mathematics (frequently with computer aid), and deserves funding and academic promotion.
Apr
1
awarded  Nice Answer
Mar
25
comment Hakenness of Heegard splitting
@IgorRivin: Ok, that clarifies things. Hyam Rubinstein gave some conditions a while back to imply that a genus 2 Heegaard splitting will have an incompressible surface in terms of the curve complex. If you like, I could try to recall that and spell it out. In some sense, the construction is a generalization of Hatcher-Thurston for incompressible surfaces in 2-bridge links.
Mar
25
answered Hakenness of Heegard splitting
Mar
24
comment algebraic varieties whose fundamental group is subgroup separable wrt subvariety subgroups
There are examples of Deligne of lattices which are not residually finite (central extensions of $Sp(2n,\mathbb{Z})$). One might be able to find such an example which is a fundamental group of an algebraic variety, and such that the center is the fundamental group of a subvariety (so it wouldn't be separable). But this is speculation - I don't know how one would carry out such a construction. However, by analogy, I know that $\tilde{Sp(2,\mathbb{Z})}= B_3$ is the fundamental group of an algebraic variety (although this case is subgroup separable). mathoverflow.net/a/79283/1345
Mar
15
comment Proofs of Bott periodicity
There's a proof of Bott periodicity Giroux gave in a talk using symplectic reduction: dl.dropboxusercontent.com/u/8592391/msri10.pdf
Mar
14
answered Nice proof of the Jordan curve theorem?
Mar
10
awarded  Necromancer
Mar
8
awarded  Announcer
Mar
8
answered Work of plenary speakers at ICM 2014
Mar
8
comment Triple bubble conjecture: Natural candidate?
Have you tried google image search? The first image that came up for me was a picture of the triple bubble, with the search "triple bubble conjecture".
Mar
4
awarded  Nice Answer
Feb
28
revised Immersed Seifert surfaces of minimal genus
added 562 characters in body
Feb
28
answered Immersed Seifert surfaces of minimal genus
Feb
27
comment Locally finite compact groups
Ok, I fixed that. In any case, it appears that the question reduces to whether there are infinite torsion pro-p groups.
Feb
27
revised Locally finite compact groups
deleted 12 characters in body