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 answers only not deleted user 7410

Questions about the branch of combinatorics called graph theory (not to be used for questions concerning the graph of a function). This tag can be further specialized via using it in combination with more specialized tags such as extremal-graph-theory, spectral-graph-theory, algebraic-graph-theory, topological-graph-theory, random-graphs, graph-colorings and several others.

7 votes
Accepted

Matrix-tree theorem for inverse matrices

There is a formula as a sum of forests, i.e., collections of trees, for arbitrary minors of any size and row/column selection, for arbitrary matrices. So it can be applied for the numerator and the de …
Abdelmalek Abdesselam's user avatar
2 votes
Accepted

Drunken X-mas polynomials for graphs

There is quite a bit of literature in statistical mechanics on spatially random permutations. The partition function essentially is $P_\Gamma(x)$ with $x=e^{-\alpha}$ for some temperature like paramet …
Abdelmalek Abdesselam's user avatar
5 votes

Number of spanning forests in a graph

I am surprised no one mentioned the work of Alan Sokal and coworkers on precisely this issue of weighted enumeration of spanning forests which is related to the $q\rightarrow 0$ limit of the Potts mod …
Harry Richman's user avatar
1 vote
Accepted

How to prove that for the real stable characteristic polynomial $P=\Phi_T$ of a tree $T$, $P...

Let $B$ denote the $n\times n$ matrix $I_x-A$. Let $[n]=\{1,2,\ldots,n\}$. For $I,J\subset [n]$ with the same number of elements, let $D_{I,J}$ denote the determinant of the matrix resulting from $B$ …
Abdelmalek Abdesselam's user avatar
5 votes

Proofs where higher dimension or cardinality actually enabled much simpler proof?

An example in the spirit (in fact a generalization) of the answer by Sam T is the triviality of the $\phi^4$ quantum field theories from lattice approximations. In dimension 5 or more this was done a …
Abdelmalek Abdesselam's user avatar
3 votes

For what graph does the following algebraic property hold?

I don't know about the literature on your specific problem but I know this arises as a trivial subquestion of a more general one for which there is literature, most of it from the 19th century. Let …
Abdelmalek Abdesselam's user avatar
2 votes

Concepts of criticality in graph theory

I think the graph studied in my article "16,051 formulas for Ottaviani's invariant of cubic threefolds" with Christian Ikenmeyer and Gordon Royle fits the bill. In the paper we considered a hypergraph …
Abdelmalek Abdesselam's user avatar
6 votes

The matrix tree theorem for weighted graphs

One can use the matrix-tree theorem with a suitable weight in order to compute the resultant of two polynomials in one variable. This is done in this 1908 article by Arthur Lee Dixon. There is also an …
Abdelmalek Abdesselam's user avatar
2 votes

Enumeration of graphs arising in invariant theory

The number ${\rm dim}\ V_{n,v,e}$ is the number of linearly independent covariants of degree $v$ and weight $e$ of a binary form of degree $n$. This is the multiplicity of the irreducible module $Sym^ …
Abdelmalek Abdesselam's user avatar