Arrow Contraction and Expansion in Tropical Diagrams

05/08/2019

∙

by   Rostislav Matveev, et al.

∙

0

∙

share

Arrow contraction applied to a tropical diagram of probability spaces is a modification of the diagram, replacing one of the morphisms by an isomorphims, while preserving other parts of the diagram. It is related to the rate regions introduced by Ahlswede and Körner. In a companion article we use arrow contraction to derive information about the shape of the entropic cone. Arrow expansion is the inverse operation to the arrow contraction.