Infinite stable graphs with large chromatic number
نویسندگان
چکیده
We prove that if $G=(V,E)$ is an $\omega$-stable (respectively, superstable) graph with $\chi (G)>\aleph _0$ $2^{\aleph _0}$) then $G$ contains all the finite subgraphs of shift $\mathrm {Sh}_n(\omega )$ for some $n$. a variant this theorem graphs interpretable in stationary stable theories. Furthermore, $\operatorname {U}(G)\leq 2$ we $n\leq suffices.
منابع مشابه
On Chromatic Number of Infinite Graphs
In our paper [1.] using a special set-theoretical construction assuming the generalized continuum hypothesis (G.C.H . in what follows) we proved that the topological product of J~k discrete topological spaces of power J~ o is not k-compact for every k < co . Since then several related or equivalent problems were independently discussed in the literature . General results of A . TARSKI, P. HANF ...
متن کاملGraphs with Large Distinguishing Chromatic Number
The distinguishing chromatic number χD(G) of a graph G is the minimum number of colours required to properly colour the vertices of G so that the only automorphism of G that preserves colours is the identity. For a graph G of order n, it is clear that 1 6 χD(G) 6 n, and it has been shown that χD(G) = n if and only if G is a complete multipartite graph. This paper characterizes the graphs G of o...
متن کاملThe locating-chromatic number for Halin graphs
Let G be a connected graph. Let f be a proper k -coloring of G and Π = (R_1, R_2, . . . , R_k) bean ordered partition of V (G) into color classes. For any vertex v of G, define the color code c_Π(v) of v with respect to Π to be a k -tuple (d(v, R_1), d(v, R_2), . . . , d(v, R_k)), where d(v, R_i) is the min{d(v, x)|x ∈ R_i}. If distinct vertices have distinct color codes, then we call f a locat...
متن کاملHadwiger's conjecture for graphs with infinite chromatic number
We construct a connected graph H such that (1) χ(H) = ω; (2) Kω, the complete graph on ω points, is not a minor of H . Therefore Hadwiger’s conjecture does not hold for graphs with infinite coloring number. 1. Notation In this note we are only concerned with simple undirected graphs G = (V,E) where V is a set and E ⊆ P2(V ) where P2(V ) = { {x, y} : x, y ∈ V and x 6= y } . We also require that ...
متن کاملGraphs With Large Girth And Large Chromatic Number
In the first part of these notes we use a probabilistic method to show the existence of graphs with large girth and large chromatic number. In the second part we give an explicit example of such graphs. It is mostly based on the third chapter of Some Applications Of Modular Forms by Peter Sarnak and also the third and forth chapters of Elementary Number Theory, Group Theory, And Ramanujan Graph...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 2021
ISSN: ['2330-0000']
DOI: https://doi.org/10.1090/tran/8570