Measurement of disorder in non-periodic sequences

Abstract
An information theoretic measure is introduced to compare the disorder in non-periodic sequences. It is shown that the measure correctly distinguishes quasiperiodic and aperiodic sequences which have been deduced from earlier studies using diffraction patterns, although it is often necessary to use a set of measures, depending on the order of the source used. The particular sequences studied are the Thue-Morse sequence and the generalizations of the golden mean sequence commonly studied in connection with quasicrystals.