bio  website  math.berkeley.edu/~ianagol 

location  Berkeley  
age  45  
visits  member for  5 years, 10 months 
seen  22 hours ago  
stats  profile views  12,707 
I'm a professor at UC Berkeley working predominantly in the field of lowdimensional topology.
15h

awarded  Nice Answer 
Aug
19 
comment 
Questions on poincare homology spheres and branched covers
You can use the orbifold theorem to answer Question 1. en.wikipedia.org/wiki/William_Thurston#Orbifold_theorem 
Aug
13 
comment 
Negatively curved metrics minimizing the length of a homotopy class of simple closed curves
By the precompactness theorem  see the third paragraph. 
Aug
5 
awarded  Enlightened 
Jul
31 
answered  Hausdorff Dimensions of Limit set of subgroups of SL(2,Z) 
Jul
30 
comment 
Surgery along an arc connecting the components of a $2$component link gives the unknot
I think this observation underlies the other papers I linked to. 
Jul
30 
comment 
Surgery along an arc connecting the components of a $2$component link gives the unknot
Hey Jim  the paper has nothing to do with Schoenfies  it's about 2spheres embedded in $\mathbb{R}^4$ with 4 critical points. Saying such a sphere is standard is equivalent to saying that any band sum of the 2component unlink which gives the unknot is standard. Scharlemann proves this actually for split links. A simpler proof was found later by Thompson. dx.doi.org/10.1016/00409383(87)900607 
Jul
30 
revised 
Surgery along an arc connecting the components of a $2$component link gives the unknot
added 368 characters in body 
Jul
30 
answered  Surgery along an arc connecting the components of a $2$component link gives the unknot 
Jul
28 
awarded  Nice Answer 
Jul
28 
comment 
Is every nonabelian finite simple group a quotient of a triangle group $(a,b,c)$ with $a,b,c$ coprime?
I believe most finite simple groups are generated by elements of order 2 and 3, which addresses the 2nd part of your question. mathoverflow.net/a/59300/1345 
Jul
28 
revised 
Intuition behind the Morse inequalities?
added 5 characters in body 
Jul
27 
answered  Intuition behind the Morse inequalities? 
Jul
21 
comment 
Torsion in profinite groups
By intersect trivial, you mean intersect in the identity element? I don't see why this follows from pointset topology. 
Jul
21 
comment 
Torsion in profinite groups
Maybe you can expand the argument in your fourth sentence  I don't understand why one has only finitely many conjugates to intersect in the identity. 
Jul
15 
awarded  Enlightened 
Jul
15 
awarded  Nice Answer 
Jul
15 
comment 
the space of continuous maps between 3manifolds
This was explained here: mathoverflow.net/a/19562/1345 
Jul
9 
answered  Your favorite papers on geometric group theory 
Jul
2 
awarded  Nice Answer 