Wright State University
Daylon, Ohio, U. S. A.
The customary tool for modeling the magnetic hysteresis loop in high temperature superconductors has been the critical state model with flux creep dissipation. Recent experimental work using magneto-optic imaging, including the discovery of ``macroturbulence'', has shown that for some temperature ranges this model is not correct, and misrepresents modeling of the magnetic hysteresis loop. In this talk we will present some recently developed ideas and show the agreement with experiment.