Learning Spaces and Media

A ‘medium’ is a collection of transformations on a set of states, specified by two constraining axioms. The term ‘medium’ stems from the original intuition suggesting such a structure, which is that of a system exposed to a bombardment of bits of information, each of which is capable of modifying its state in a minute way 1997. The system could be, for example an individual subjected to a barrage of messages from the media—that is, the press in all its incarnations—regarding the candidates in an election (see Regenwetter, Falmagne, and Grofman, 1999, for a good example). An account of such an application is Falmagne, Hsu, Leite, and Regenwetter (2007).