Interplay Between Linear and Nonlinear Processes in Simulation and Space Plasmas

Over the last few decades, two different theoreticalframeworks have been developed to study formation and evolution of space plasmas such as the solar wind and terrestrial magnetosheath. One uses linear Vlasov theory to explore micro-scale phenomena: the effects of waves and the constraints imposed by microinstabilities on the plasmas. The other includes the larger mesoscales and focuses on non-linear processes such as turbulence and the coherent structures it generates. These two processes occur simultaneously in both space and time and are entangled together at different scales. Consequently, there is an implied competition between the two processes to determine which one dominates given a set of conditions in the space plasmas. We look at the two processes simultaneously, using the associated time scales in six different datasets (3 fully kinetic PIC simulations and 3 spacecraft observations) to see the result of this competition as well as the dynamics between the two. We compare the time scales of two processes to see which one dominates and report our results. We also explore why linear theory seems to work in space plasmas as well as it does.