Convergence analysis of a discontinuous Galerkin/Strang splitting approximation for the Vlasov--Poisson equations

A rigorous convergence analysis of the Strang splitting algorithm with a discontinuous Galerkin approximation in space for the Vlasov–Poisson equations is provided. It is shown that under suitable assumptions the error is of order $\mathcal{O}({\tau }^2+h^q+h^q\mathrm{/}\tau )$, where $\tau$ is the size of a time step, $h$ is the cell size, and $q$ the order of the discontinuous Galerkin approximation. In order to investigate the recurrence phenomena for approximations of higher order as well as to compare the algorithm with numerical results already available in the literature a number of numerical simulations are performed.