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arXiv · 1712.09377

Variational order for forced Lagrangian systems

D. Martín de Diego·R. Sato Martín de Almagro
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Abstract

We are able to derive the equations of motion for forced mechanical systems in a purely variational setting, both in the context of Lagrangian or Hamiltonian mechanics, by duplicating the variables of the system as introduced by Galley [2013], Galley, Tsang, and Stein [2014]. We show that this construction is useful to design high-order integrators for forced Lagrangian systems and, more importantly, we give a characterization of the order of a method applied to a forced system using the corresponding variational order of the duplicated one.

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D. Martín de Diego, R. Sato Martín de Almagro. 2017-12-26. Variational order for forced Lagrangian systems. https://doi.org/10.1088/1361-6544%2Faac5a6

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