Solutions to the cosmic ray Fokker-Planck equation and time dependent diffusion coefficients
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For over a century the complicated nature of cosmic rays has provided mankind with many unanswered questions. Due to the non linear nature of turbulent magnetic fields and their interaction with charged particles there has been a mathematical struggle in the scientific community to find answers to some of these questions. In this thesis, the fundamental equation of cosmic ray propagation (the Fokker-Planck equation) is examined alongside its properties. The solution to this equation is found numerically, as well as approximated analytically, and the most popular models for the undetermined, Fokker-Planck scattering coefficient, are examined. As well, the perpendicular diffusion coefficients that drive the nature of cosmic ray propagation are examined by using the most contemporary theoretical model, time dependent UNLT theory. This theory demands assumptions for both the magnetic correlation tensor and the particle distribution function, therefore the most commonly made assumptions for each are explored.