bio  website  math.berkeley.edu/~ianagol 

location  Berkeley  
age  43  
visits  member for  4 years, 5 months 
seen  9 hours ago  
stats  profile views  10,688 
I'm a professor at UC Berkeley working predominantly in the field of lowdimensional topology.
10h

comment 
Cohomological Proof of Serre Relations for a Symmetrizable KacMoody 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 KacMoody algebras from vertex algebras. So this might be a good warmup. 
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?
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2d

answered  Can finitely generated subgroups of limit groups be detected in free group quotients? 
Apr 15 
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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 
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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 HatcherThurston for incompressible surfaces in 2bridge 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 
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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 
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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
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Feb 28 
answered  Immersed Seifert surfaces of minimal genus 
Feb 27 
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Locally finite compact groups
Ok, I fixed that. In any case, it appears that the question reduces to whether there are infinite torsion prop groups. 
Feb 27 
revised 
Locally finite compact groups
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