Introduction

Abstract

Hysteresis occurs in several phenomena. In physics we encounter it in plasticity, friction, ferromagnetism, ferroelectricity, superconductivity, adsorption and desorption, for instance. More generally, hysteresis arises in phase transitions, a typical example being undercooling effects prior to nucleation. Shape memory effects have been observed and exploited in some recently developed materials. Hysteresis also occurs in engineering; thermostats are a very usual example. Others are met in porous media filtration, granular motion, semiconductors, spin glasses, mechanical damage and fatigue, for instance. Hysteresis also appears in chemistry, biology, economics, even in experimental psychology, and so on.