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arXiv · 1505.05411

Modified Equations for Variational Integrators

Mats Vermeeren
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Abstract

It is well-known that if a symplectic integrator is applied to a Hamiltonian system, then the modified equation, whose solutions interpolate the numerical solutions, is again Hamiltonian. We investigate this property from the variational side. We present a technique to construct a Lagrangian for the modified equation from the discrete Lagrangian of a variational integrator.

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Mats Vermeeren. 2016-06-22. Modified Equations for Variational Integrators. https://doi.org/10.1007/s00211-017-0896-4

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