Spice the Bird's user avatar
Spice the Bird's user avatar
Spice the Bird's user avatar
Spice the Bird
  • Member for 12 years, 11 months
20 votes
2 answers
2k views

If $X$ is a simplicial complex, is there a characterization of the links of its vertices that is equivalent to the statement "$|X|$ is a manifold"?

6 votes
4 answers
2k views

What is the intuition of connections for cubical sets?

17 votes
2 answers
1k views

What is the homotopy type of the space of the homeomorphisms of the n-ball whose restriction to the boundary is isotopic to the identity?

13 votes
5 answers
1k views

Is the following invariant of rooted trees a complete invariant?

5 votes
2 answers
702 views

A subcategory of top where subspaces and subobjects coincide?

3 votes
1 answer
495 views

What is the chromatic number of the graph whose vertices dimension $n-2$ subsimplicies of $\Delta^n$ and an edge between two vertices is given if the two associated $n-2$ vertices are contained in the same $n-1$ subsimplex?

11 votes
1 answer
478 views

What is the precise relationship between "prodsimplicial sets" and rooted trees?

4 votes
2 answers
398 views

Is it possible to define the notion of a localization of a category without reference to a set of morphisms, $S$?

3 votes
3 answers
383 views

Are the categories, $\widehat{\mathcal{A}}\downarrow X$ and $\widehat{\mathcal{A}\downarrow X}$ equivalent.

3 votes
1 answer
325 views

Does each "prod-simplicial" regular cell complex come from a unique rooted tree?

5 votes
0 answers
161 views

What propositions about sets can be transfered to propositions about a presheaf category?