A Tutorial on Variational Integrators

Stephen D. Webb

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arXiv · 1409.5090

A Tutorial on Variational Integrators

Stephen D. Webb

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Abstract

We present a brief tutorial on the nuts and bolts computation of a multisymplectic particle-in-cell algorithm using the discretized Lagrangian approach. This approach, originated by Marsden, Shadwick, and others, brings the benefits of symplectic integration of Hamiltonian systems to full electromagnetic particle-in-cell algorithms. To make the work more approachable, we present a basic discussion of the philosophy, combined with a detailed derivation of a standard 1-dimensional electrostatic particle-in-cell algorithm.

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Stephen D. Webb. 2014-09-13. A Tutorial on Variational Integrators. https://arxiv.org/abs/1409.5090

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