What’s hot at mathoverflow 15/17
Intuition for symplectic groups A refinement of Serre’s finiteness theorem on unstable homotopy groups of spheres Exotic 4-spheres and the Tate-Shafarevich Group Does every compact metric space have a...
View ArticleWhat’s hot at mathoverflow 16/17
Finite-order self-homeomorphisms of \({\mathbb R}^n\) Measuring a presheaf’s failure to be a sheaf? The geometry of the solution set of a symmetric equation in four symmetric matrices A search for a...
View ArticleWhat’s hot at mathoverflow 17/17
3D Billiards problem inside a torus 71, the Monster, and c = 24 CFTs What’s with equivariant homotopy theory over a compact Lie group? Kodaira-Spencer maps and deformation theory Solving ODE via...
View ArticleWhat’s hot at mathoverflow 18/17
Open subsets of Euclidean space in dimension 5 and higher admitting exotic smooth structures Can a finite group action by homeomorphisms of a three-manifold be approximated by a smooth action? Can a...
View ArticleWhat’s hot at mathoverflow 19/17
Is there a geometric interpretation for Reidemeister torsion? Quillen + construction for finite groups An abstract nonsense proof of the Hurewicz theorem How should I formalize that there’s no...
View ArticleWhat’s hot at mathoverflow 20/17
Why is the definition of higher homotopy groups the “right one”? Why is there no symplectic version of spectral geometry? Pullback and homology Is this generalization of Borsuk-Ulam true? Roots of...
View ArticleWhat’s hot at mathoverflow 21/2017
Concepts in topology successfully transferred to graph theory and combinatorics with non-trivial applications? Is there a “universal” connected compact metric space? A short proof for simple...
View ArticleWhat’s hot at math overflow 22/2017
Concepts in topology successfully transferred to graph theory and combinatorics with non-trivial applications? Automorphisms of genus 6 surfaces Finiteness aspects of Deligne cohomology Tubular...
View ArticleWhat’s hot at MathOverflow 23/2017
The two ways Feynman diagrams appear in mathematics Relationships between homology maps of cobordant manifolds Sullivan conjecture for compact Lie groups Quasi-isometric groups without common virtual...
View ArticleValidity of results, II
In July I wrote a post about Validity of results. It was about a recent preprint pointing out an erroneous proof in an influential paper. By chance I stumbled yesterday upon this question on...
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