Ilya Grigoriev's user avatar
Ilya Grigoriev's user avatar
Ilya Grigoriev's user avatar
Ilya Grigoriev
  • Member for 14 years, 5 months
  • Last seen more than a month ago
24 votes
7 answers
4k views

Why are two notions of Gaussian curvature are the same - what is the simplest & most didactic proof?

17 votes
4 answers
3k views

Finding Constant Curvature Metrics on Surfaces without full power of Uniformization

16 votes
2 answers
2k views

Why is every symplectomorphism of the unit disk Hamiltonian isotopic to the identity?

14 votes
4 answers
2k views

When do two holonomy maps determine flat bundles that are isomorphic as just bundles (w/o regard to the flat connections)?

9 votes
3 answers
1k views

Can homologous submanifolds be connected by an immersed manifold with boundary?

2 votes
2 answers
1k views

Why (and whether) is any smooth embedded torus in R^4 isotopic to an embedded Lagrangian torus?

8 votes
2 answers
809 views

Weil's theorem about maps from a discrete group to a Lie group.

5 votes
2 answers
621 views

Definition of the Kervaire invariant for normal maps (as in Browder's book)

6 votes
1 answer
444 views

The (n+1)-st cohomology of K(Z/p,n).

4 votes
0 answers
265 views

Action of the mapping class group on separating spheres in a connected sum of aspherical 3-manifolds