Edited by:
C. Chandre
E. Tassi
J.-L. Thiffeault

This special issue of Communications in Nonlinear Sciences and Numerical Simulation celebrates the career of Professor Philip J. Morrison, whose research contributes to both mathematical physics and theoretical physics and is usually motivated by problems arising in plasma physics, geophysical fluid dynamics, or general fluid dynamics.

This special issue consists of papers by former students and long time collaborators. The broad range of topics reflects the diversity of his interests. It comes as no surprise that a significant number of the contributions originates from plasma physics, in particular in the Hamiltonian formulation of kinetic and fluid models, the numerical investigation of instabilities in plasmas, and the structure of magnetic field lines and equilibria. Related contributions deal also with the analysis of Hamiltonian systems and dynamical instabilities in fluid mechanics, and in particular geophysical fluids. Another group of contributions reflects Professor Morrison’s interests for lower- dimensional systems with a precise analysis of the dynamical structure of phase space and reduction methods with some emphasis on nontwist maps.