 Haran's diamond theorem

Haran's diamond theorem is a result in set theory and the study of topology, specifically dealing with the properties of certain types of topological spaces. The theorem pertains to the concept of "diamonds," which are specific kinds of ordered sets that can encode certain structures in topology. The primary assertion of Haran's diamond theorem characterizes the conditions under which one can embed a specific kind of ordered structure (notably the diamond principle) into a larger structure.