Physical Characterization of the Dynamics of Amorphous Condensed Matter

Eleven main characteristics of the dynamics of amorphous materials are listed and described, to define what must be explained and therefore stand as the ultimate goals of any comprehensive theory of their behavior. Some of the characteristics are easily recognized and may be described in simple terms, while others will require more elaborate discussion, in view of either their long-recognized theoretical and practical importance, still disputed origin, or special emphasis in the most recent theoretical developments. In the second group of characteristics, we include the sensitivity toTemperaturesensitivity to temperatureTemperature and to the molecular packingMolecular packing (where two conflicting views may be held, or in some way considered complementary), the cooperativityCooperativity and dynamic heterogeneityDynamic heterogeneity of the materials’ response, the universalityUniversality of their behavior, and hysteresisHysteresis and agingAging effects, whose discussion will however only approach (though of course not yet reaching) completion in conjunction with the content and results of Chaps. 8 – 12 and 14 .