User Piero D'Ancona

88 votes

Examples of interesting false proofs

answered Apr 22, 2012 at 10:52

81 votes

Generalizing a problem to make it easier

answered Sep 26, 2010 at 10:27

44 votes

Examples of advance via good definitions

answered Mar 2, 2017 at 11:14

39 votes

The role of completeness in Hilbert Spaces

answered Aug 18, 2010 at 19:26

25 votes

Facts from algebraic geometry that are useful to non-algebraic geometers

answered Aug 23, 2010 at 20:47

25 votes

Motivation for and history of pseudo-differential operators

answered Mar 22, 2011 at 15:04

21 votes

Dual of the space of Hölder continuous functions?

answered Apr 10, 2012 at 17:45

19 votes

Should one attack hard problems?

answered Mar 11, 2013 at 8:44

18 votes

Accepted

Continuous + holomorphic on a dense open => holomorphic?

answered Aug 8, 2010 at 23:15

18 votes

Computer algebra errors

answered Aug 9, 2010 at 21:15

17 votes

Why is the Laplacian ubiquitous?

answered Feb 10, 2011 at 16:47

14 votes

Interesting conjectures "discovered" by computers and proved by humans?

answered Mar 25, 2012 at 18:28

13 votes

Axiom of choice, Banach-Tarski and reality

answered Jan 20, 2017 at 8:14

13 votes

Every mathematician has only a few tricks

answered Jun 15, 2020 at 18:55

12 votes

Mathematicians with both “very abstract” and “very applied” achievements

answered Jan 2, 2020 at 9:38

12 votes

Explicit computations using the Haar measure

answered Aug 18, 2010 at 21:55

11 votes

Quick proofs of hard theorems

answered Jul 11, 2010 at 9:12

11 votes

Accepted

Chain rule in Sobolev space

answered Sep 13, 2022 at 5:55

11 votes

Are Fourier transforms of L^p stable under diffeomorphisms?

answered Aug 18, 2016 at 23:10

11 votes

Sobolev spaces and geometry

answered Mar 5, 2014 at 18:12

10 votes

Structures that turn out to exhibit a symmetry even though their definition doesn't

answered Jan 13, 2014 at 8:59

10 votes

Comparison of two versions of fractional Sobolev spaces: do we have $W^{s,p}(\mathbb{R}^{n})=H^{s,p}(\mathbb{R}^{n})$?

answered Dec 16, 2017 at 17:41

10 votes

Riemannian surfaces with an explicit distance function?

answered Sep 4, 2010 at 11:35

10 votes

Can a self-adjoint operator have a continuous set of eigenvalues?

answered Sep 25, 2010 at 11:30

10 votes

The Cauchy–Riemann equations and analyticity

answered Oct 6, 2010 at 9:08

10 votes

Manifold-Valued Sobolev Spaces

answered Jul 12, 2012 at 7:59

10 votes

Famous mathematicians with background in arts/humanities/law etc

answered Sep 28, 2011 at 20:56

9 votes

Does Physics need non-analytic smooth functions?

answered Nov 26, 2012 at 19:25

8 votes

Accepted

Interpolation of Sobolev spaces

answered Feb 8, 2011 at 17:51

8 votes

Accepted

A good reference for the wave front set

answered Dec 3, 2010 at 14:39

Stack Exchange Network

150 Answers

Examples of interesting false proofs

Generalizing a problem to make it easier

Examples of advance via good definitions

The role of completeness in Hilbert Spaces

Facts from algebraic geometry that are useful to non-algebraic geometers

Motivation for and history of pseudo-differential operators

Dual of the space of Hölder continuous functions?

Should one attack hard problems?

Continuous + holomorphic on a dense open => holomorphic?

Computer algebra errors

Why is the Laplacian ubiquitous?

Interesting conjectures "discovered" by computers and proved by humans?

Axiom of choice, Banach-Tarski and reality

Every mathematician has only a few tricks

Mathematicians with both “very abstract” and “very applied” achievements

Explicit computations using the Haar measure

Quick proofs of hard theorems

Chain rule in Sobolev space

Are Fourier transforms of L^p stable under diffeomorphisms?

Sobolev spaces and geometry

Structures that turn out to exhibit a symmetry even though their definition doesn't

Comparison of two versions of fractional Sobolev spaces: do we have $W^{s,p}(\mathbb{R}^{n})=H^{s,p}(\mathbb{R}^{n})$?

Riemannian surfaces with an explicit distance function?

Can a self-adjoint operator have a continuous set of eigenvalues?

The Cauchy–Riemann equations and analyticity

Manifold-Valued Sobolev Spaces

Famous mathematicians with background in arts/humanities/law etc

Does Physics need non-analytic smooth functions?

Interpolation of Sobolev spaces

A good reference for the wave front set