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Adam Chalumeau
  • Member for 3 years, 3 months
  • Last seen this week
  • Strasbourg, France
25 votes
2 answers
1k views

Find $f$ such that $f^{-1}(\lbrace0\rbrace)$ is this knotted curve (M.W.Hirsh)

10 votes
1 answer
415 views

Affine manifolds which are not euclidean manifolds.

9 votes
1 answer
183 views

Is the smallest ball enclosing a compact a Lipschitz function of the compact?

8 votes
2 answers
264 views

What are some examples of incomplete nonextendible manifolds?

7 votes
1 answer
165 views

Local obstruction to having a complete extension

7 votes
1 answer
307 views

Are products of spheres $\prod_i\Bbb S^{n_i}$ different?

6 votes
1 answer
189 views

Is the splitting $\pi_{k}(X,A)\simeq\pi_{k}(X)\times \pi_{k-1}(A)$ a $\pi_1(A)$-modules isomorphism?

6 votes
2 answers
144 views

Codimension one foliations induced by a map to the circle.

5 votes
1 answer
435 views

About Poincaré-Hopf theorem: can we find and draw $v$ with only one zero on $S$?

4 votes
1 answer
123 views

Condition for a quotient map to have compact image.

4 votes
1 answer
132 views

$5$-dimensional irreducible representation of $\mathcal{A}_5$

3 votes
1 answer
110 views

Submersions from $\Bbb T^2$ to $\Bbb S^1$.

2 votes
0 answers
36 views

Inhomogeneous complete affine manifolds

2 votes
1 answer
95 views

Is the Ricci tensor of a symmetric space proportional to the killing form?

2 votes
1 answer
208 views

$\Bbb{S}^1$-bundle over $\Bbb{S}^1$ + reference request

2 votes
1 answer
86 views

Induced morphism on automorphism groups in terms of the original map.

2 votes
1 answer
77 views

$A=\lambda I_n\iff (\forall M,N\in M_n(\mathbb{R}),~ MN=A \Rightarrow ~ NM=A)$

1 vote
0 answers
92 views

What are the possible Lie algebras of $K=\rho(\mathbb{R}^2)$, where $\rho :\mathbb{R}^2\to \text{Aff}(\mathbb{R}^2)$?

1 vote
0 answers
87 views

The projective geometry contains the affine geometry

1 vote
2 answers
71 views

Definition of Cartan subalgebra in Erdmann-Wildon