Question

Is collapsing a contractible closed subspace a homotopy equivalence?

score 101 · Answer 1 · 2026-04-11 22:31:24

101

Views

Is collapsing a contractible closed subspace a homotopy equivalence?

Published on 11 Apr 2026 - 22:31

score 126 · Answer 2 · 2026-03-28 06:01:00

126

Views

Unit Spheres, Isotopies, and Homotopies

Published on 28 Mar 2026 - 6:01

score 269 · Answer 3 · 2026-03-25 01:20:27

269

Views

Weak homotopy equivalence between $\Omega \underset{\rightarrow}{\lim} \ Z_n$ and $\underset{\rightarrow}{\lim} \ \Omega Z_n$

Published on 25 Mar 2026 - 1:20

score 204 · Answer 4 · 2026-03-30 07:11:23

204

Views

How to define 0-sphere in a category with zero object?

Published on 30 Mar 2026 - 7:11

score 170 · Answer 5 · 2026-04-05 22:33:38

170

Views

Goodwillie Calculus II (5.2)

Published on 05 Apr 2026 - 22:33

score 957 · Answer 6 · 2026-04-11 03:26:11

957

Views

Cofibrations are embeddings

Published on 11 Apr 2026 - 3:26

score 102 · Answer 7 · 2026-04-09 03:51:43

102

Views

Compact 3-dimensional extension of two-dimensional torus

Published on 09 Apr 2026 - 3:51

score 130 · Answer 8 · 2026-04-12 13:56:05

130

Views

The identity homotopy on the circle can create an arc of any length

Published on 12 Apr 2026 - 13:56

score 33 · Answer 9 · 2026-04-11 04:39:49

33

Views

Fundamental group of a plane united with a circle in 3D space

Published on 11 Apr 2026 - 4:39

score 144 · Answer 10 · 2026-04-06 01:55:06

144

Views

If $(X,A)$ has homotopy extension property, then $(X \times I, X \times \partial I \cup A \times I)$ also shares this property.

Published on 06 Apr 2026 - 1:55

score 445 · Answer 11 · 2018-10-20 01:09:23

445

Views

If $X$ is the retract of its cone $CX$ it is contractible

Published on 20 Oct 2018 - 1:09

score 405 · Answer 12 · 2026-04-06 01:51:07

405

Views

What is the difference between $D(\mathbb Z)$ and $Spectra$ in terms of $t$-structures?

Published on 06 Apr 2026 - 1:51

score 590 · Answer 13 · 2026-04-11 07:45:50

590

Views

the Euler characteristic of $K\#K$

Published on 11 Apr 2026 - 7:45

score 533 · Answer 14 · 2026-04-06 01:58:49

533

Views

Space with semi-locally simply connected open subsets

Published on 06 Apr 2026 - 1:58

score 1.3k · Answer 15 · 2026-03-25 04:40:47

1.3k

Views

Homotopy type of the diffeomorphism group of the sphere.

Published on 25 Mar 2026 - 4:40

List Question

Is collapsing a contractible closed subspace a homotopy equivalence?

Unit Spheres, Isotopies, and Homotopies

Weak homotopy equivalence between $\Omega \underset{\rightarrow}{\lim} \ Z_n$ and $\underset{\rightarrow}{\lim} \ \Omega Z_n$

How to define 0-sphere in a category with zero object?

Goodwillie Calculus II (5.2)

Cofibrations are embeddings

Compact 3-dimensional extension of two-dimensional torus

The identity homotopy on the circle can create an arc of any length

Fundamental group of a plane united with a circle in 3D space

If $(X,A)$ has homotopy extension property, then $(X \times I, X \times \partial I \cup A \times I)$ also shares this property.

If $X$ is the retract of its cone $CX$ it is contractible

What is the difference between $D(\mathbb Z)$ and $Spectra$ in terms of $t$-structures?

the Euler characteristic of $K\#K$

Space with semi-locally simply connected open subsets

Homotopy type of the diffeomorphism group of the sphere.

Trending Questions

Popular # Hahtags

Popular Questions