User Eric Wofsey

11 votes

Accepted

Category which has no non-trivial adjoint functors

answered Aug 9, 2014 at 17:46

11 votes

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The natural inclusion of an infinite abelian group $G$ into $\widehat{\widehat{G}}$

answered Mar 1, 2011 at 2:28

11 votes

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Compact MU or BP Modules

answered Dec 14, 2012 at 23:55

10 votes

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"Skew Cohomology" of a Space

answered Mar 4, 2011 at 2:17

10 votes

Are there two non-diffeomorphic smooth manifolds with the same homology groups?

answered Oct 30, 2009 at 4:02

10 votes

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Must the union of these two aspherical spaces be aspherical?

answered Oct 1, 2013 at 5:39

10 votes

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Can the group of homotopy classes of maps into S^3 be noncommutative?

answered Mar 14, 2014 at 2:42

10 votes

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Must a closed totally path-disconnected subset of the sphere have connected complement?

answered Mar 24, 2014 at 14:18

10 votes

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Partial Orders realized by Prime Ideals on commutative rings

answered Jan 29, 2016 at 12:42

9 votes

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Pontryagin dual of the surreal numbers?

answered Sep 23, 2015 at 23:25

9 votes

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On the Riesz representation theorem

answered Aug 24, 2015 at 16:33

9 votes

Under what conditions $\|x-y\|=n\iff\|f(x)-f(y)\|=n.$ for $n\in\mathbf{N}$ implies isometry?

answered Jan 24, 2015 at 3:04

9 votes

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Isomorphisms and higher homotopy

answered May 2, 2014 at 14:21

9 votes

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Maximum cardinality of a filtered limit of finite sets

answered Jun 26, 2014 at 13:04

9 votes

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Is a conservative finite limit preserving functor of (infinity,1)-categories homotopically faithful?

answered Dec 31, 2012 at 17:47

9 votes

(how) are vector bundles and homotopy groups related?

answered Oct 26, 2009 at 20:47

9 votes

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Does Cantor-Bernstein hold for classes?

answered Oct 19, 2009 at 1:17

8 votes

Does the "continuous locus" of a function have any nice properties?

answered Oct 7, 2009 at 3:02

8 votes

When does the sheaf direct image functor f_* have a right adjoint?

answered Oct 27, 2009 at 20:58

8 votes

Subcategories of abelian categories generated by finitely many objects

answered Mar 13, 2012 at 19:26

8 votes

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How equivalent are the theories of reduced and groupal $\infty$-groupoids?

answered Feb 26, 2011 at 23:56

8 votes

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Irreducible cohomology theories

answered Jan 4, 2013 at 16:43

8 votes

Why all irreducible representations of compact groups are finite-dimensional ? [EDIT: Subtleties: AC,etc]

answered Jan 20, 2013 at 19:55

8 votes

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Are there examples of families of objects which are canonically isomorphic, but where diagrams of canonical isomorphisms don't commute?

answered Oct 23, 2014 at 1:56

8 votes

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Homotopy factorization of morphisms of chain complexes

answered Jun 2, 2014 at 20:15

8 votes

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Compactly supported cohomology of homotopy equivalent manifolds

answered Apr 2, 2014 at 2:08

8 votes

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The first element in the stable homotopy of a $K(\mathbb{Z}/2, n)$

answered Nov 6, 2013 at 3:52

8 votes

Does k(X) have a k-basis for every set X, without AC?

answered Jan 20, 2015 at 3:40

8 votes

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Exact sequence of groups to exact sequence of sheaves

answered Feb 19, 2015 at 4:59

8 votes

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Every free abelian group is slender, why?

answered Nov 15, 2014 at 21:26

Stack Exchange Network

265 Answers

Category which has no non-trivial adjoint functors

The natural inclusion of an infinite abelian group $G$ into $\widehat{\widehat{G}}$

Compact MU or BP Modules

"Skew Cohomology" of a Space

Are there two non-diffeomorphic smooth manifolds with the same homology groups?

Must the union of these two aspherical spaces be aspherical?

Can the group of homotopy classes of maps into S^3 be noncommutative?

Must a closed totally path-disconnected subset of the sphere have connected complement?

Partial Orders realized by Prime Ideals on commutative rings

Pontryagin dual of the surreal numbers?

On the Riesz representation theorem

Under what conditions $\|x-y\|=n\iff\|f(x)-f(y)\|=n.$ for $n\in\mathbf{N}$ implies isometry?

Isomorphisms and higher homotopy

Maximum cardinality of a filtered limit of finite sets

Is a conservative finite limit preserving functor of (infinity,1)-categories homotopically faithful?

(how) are vector bundles and homotopy groups related?

Does Cantor-Bernstein hold for classes?

Does the "continuous locus" of a function have any nice properties?

When does the sheaf direct image functor f_* have a right adjoint?

Subcategories of abelian categories generated by finitely many objects

How equivalent are the theories of reduced and groupal $\infty$-groupoids?

Irreducible cohomology theories

Why all irreducible representations of compact groups are finite-dimensional ? [EDIT: Subtleties: AC,etc]

Are there examples of families of objects which are canonically isomorphic, but where diagrams of canonical isomorphisms don't commute?

Homotopy factorization of morphisms of chain complexes

Compactly supported cohomology of homotopy equivalent manifolds

The first element in the stable homotopy of a $K(\mathbb{Z}/2, n)$

Does k(X) have a k-basis for every set X, without AC?

Exact sequence of groups to exact sequence of sheaves

Every free abelian group is slender, why?