Johannes Ebert's user avatar
Johannes Ebert's user avatar
Johannes Ebert's user avatar
Johannes Ebert
  • Member for 13 years, 5 months
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111 votes
6 answers
10k views

Counterexamples in algebraic topology?

70 votes
6 answers
8k views

third stable homotopy group of spheres via geometry?

32 votes
1 answer
2k views

Is every ''group-completion'' map an acyclic map?

28 votes
1 answer
2k views

A question about the topological proofs of Bott periodicity

24 votes
2 answers
1k views

Good functorial model for BG

20 votes
2 answers
3k views

What is a symmetric monoidal $(\infty,n)$-category?

20 votes
0 answers
614 views

On a homological finiteness condition

19 votes
3 answers
1k views

Degrees of self-maps of aspherical manifolds

18 votes
2 answers
1k views

Karoubi versus Kasparov K-theory

17 votes
1 answer
1k views

Adams' theorems on the Hopf-Whitehead J-homomorphism

16 votes
2 answers
3k views

The fundamental group of a closed surface without classification of surfaces?

13 votes
0 answers
847 views

About maps inducing bijections on homotopy classes

12 votes
1 answer
773 views

Lie's third theorem via differential graded algebras?

8 votes
2 answers
943 views

Homotopy invariance of vector bundles by parallel transport: reference needed for my students.

6 votes
2 answers
1k views

Proof of the ''trangression theorem''