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Danny Calegari
  • Member for 12 years, 6 months
31 votes

What should be offered in undergraduate mathematics that's currently not (or isn't usually)?

25 votes

Is a subgroup of a free abelian group free abelian?

18 votes
Accepted

Circle bundles over $RP^2$

14 votes
Accepted

What is the right way to think about / represent general tilings?

13 votes
Accepted

What are CR manifolds like?

13 votes

What's an example of a space that needs the Hahn-Banach Theorem?

11 votes

Why is the standard definition of cocycle the one that _always_ comes up??

11 votes

Algorithm generalizing continued fractions for non-quadratic algebraic numbers

11 votes
Accepted

Rational Group Cohomology

8 votes

What's a non-abelian totally ordered group?

8 votes
Accepted

Independence of the continuum hypothesis on ZFC

8 votes

Is there a simplicial volume definition of Chern Simons invariants?

7 votes

When is a Riemannian metric equivalent to the flat metric on $\mathbb R^n$?

7 votes
Accepted

Dolbeault cohomology

5 votes

can you fool SnapPea?

4 votes

Stable w-length

4 votes

What is an example of a function on M_g?

3 votes

Lie Groups and Manifolds

3 votes
Accepted

Symmetrical Presentation of 4-Dimensional Rotation Matrix

2 votes

Minimal surface in a ball