Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options not deleted user 10881

The study of differentiable manifolds and differentiable maps. One fundamental problem is that of classifying manifolds up to diffeomorphism. Differential topology is what Poincaré understood as topology or “analysis situs”.

4 votes

Characteristic polynomials of trees and E8

Using sage, and up to 16 vertices included, one finds only two trees satisfying $|det(A+2I)|=1$, namely $E_8$ and $E_{10}$. EDIT: I also confirm that there are 18 such trees with 18 vertices. Here th …
F. C.'s user avatar
  • 3,597
1 vote

Computation of the Euler characteristic of a specific real variety

One possible way to compute Euler characteristic is to use its properties: $\chi$ is additive on disjoint unions $\chi$ is multiplicative on fibrations $\chi$ of the point is $1$ So one has to eit …
F. C.'s user avatar
  • 3,597