Paper detail

A Note on Edge Colorings and Trees

We point out some connections between existence of homogenous sets for certain edge colorings and existence of branches in certain trees. As a consequence, we get that any locally additive coloring (a notion introduced in the paper) of a cardinal $κ$ has a homogeneous set of size $κ$ provided that the number of colors, $μ$ satisfies $μ^+<κ$. Another result is that an uncountable cardinal $κ$ is weakly compact if and only if $κ$ is regular, has the tree property and for each $λ,μ<κ$ there exists $κ^*<κ$ such that every tree of height $μ$ with $λ$ nodes has less than $κ^*$ branches.