Ramsey cone topology
= Ramsey cone topology
{c}
{title2=$\tau_{\mathrm{cone}}$}
This topology has basic open sets $[A]^\omega$ for infinite ground sets $A$, without fixed finite stems. It is coarser than the <Ellentuck topology> and differs from the <ordinary topology on infinite subsets>, whose basic cylinders fix an initial segment. The symbol $\tau$ is sometimes used for either coarser convention, so it should be accompanied by a definition.