User Spencer

55 votes

17 answers

16k views

Computer science for mathematicians

asked Jan 5, 2011 at 16:49

41 votes

14 answers

4k views

A set for which it is hard to determine whether or not it is countable.

asked Mar 21, 2011 at 23:23

21 votes

3 answers

6k views

Why pi-systems and Dynkin/lambda systems? On the relative merits of approaches in measure theory.

asked Jul 17, 2010 at 15:07

17 votes

3 answers

3k views

Why is the harmonic oscillator so important? (pure viewpoint sought). How to motivate its role in Getzler's work on Atiyah-Singer?

asked Mar 4, 2010 at 22:05

11 votes

5 answers

4k views

Brownian motion, martingales, Markov Chains - Rosetta Stone

asked Sep 29, 2010 at 17:30

10 votes

3 answers

4k views

Is the Lie algebra-valued curvature two-form on a principal bundle P the curvature of a vector bundle over P?

asked Jun 27, 2011 at 17:33

8 votes

1 answer

289 views

Closed geodesics in free smooth loop space?

asked Apr 8, 2015 at 2:35

7 votes

4 answers

6k views

The characteristic (indicator) function of a set is not in the Sobolev space H¹

asked May 18, 2010 at 16:34

6 votes

3 answers

869 views

Divergence form Elliptic PDE Removable Singularity/Regularity Question

asked Nov 26, 2012 at 14:47

5 votes

1 answer

136 views

Reference for higher order Campanato Lemmas, e.g. `Sufficiently fast L^2 decay on balls to affine functions implies C^{1,\alpha}'

asked Mar 18, 2015 at 3:42

4 votes

2 answers

2k views

Inclusions of $C^{k,\alpha}$ spaces

asked Oct 23, 2010 at 14:30

3 votes

2 answers

238 views

What is the "real osculating space" of a (minimal) immersion?

asked Nov 28, 2012 at 11:40

3 votes

0 answers

109 views

What dimension bound is known on the singular set of a linear combination of eigenfunctions of Laplacian?

asked Jul 14, 2015 at 10:04

2 votes

2 answers

2k views

When is the group of homeomorphisms of a compact space locally compact?

asked Dec 1, 2010 at 14:50

0 votes

0 answers

104 views

Must the Lebesgue measure of a $\rho$ - neighbourhood of an $(n-2)$ - dimensional set be at least $c\rho^2$?

asked Feb 13, 2015 at 0:22

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15 Questions

Computer science for mathematicians

A set for which it is hard to determine whether or not it is countable.

Why pi-systems and Dynkin/lambda systems? On the relative merits of approaches in measure theory.

Why is the harmonic oscillator so important? (pure viewpoint sought). How to motivate its role in Getzler's work on Atiyah-Singer?

Brownian motion, martingales, Markov Chains - Rosetta Stone

Is the Lie algebra-valued curvature two-form on a principal bundle P the curvature of a vector bundle over P?

Closed geodesics in free smooth loop space?

The characteristic (indicator) function of a set is not in the Sobolev space H¹

Divergence form Elliptic PDE Removable Singularity/Regularity Question

Reference for higher order Campanato Lemmas, e.g. `Sufficiently fast L^2 decay on balls to affine functions implies C^{1,\alpha}'

Inclusions of $C^{k,\alpha}$ spaces

What is the "real osculating space" of a (minimal) immersion?

What dimension bound is known on the singular set of a linear combination of eigenfunctions of Laplacian?

When is the group of homeomorphisms of a compact space locally compact?

Must the Lebesgue measure of a $\rho$ - neighbourhood of an $(n-2)$ - dimensional set be at least $c\rho^2$?