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arXiv · 1804.08318

Long-time energy analysis of extended RKN integrators for muti-frequency highly oscillatory Hamiltonian systems

Bin Wang·Xinuan Wu
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Abstract

In this paper, we study the long-time near conservation of the total and oscillatory energies for extended RKN (ERKN) integrators when applied to muti-frequency highly oscillatory Hamiltonian systems. We consider one-stage explicit symmetric integrators and show their long-time behaviour of numerical energy conservations by using modulated multi-frequency Fourier expansions. Numerical experiments are carried out and the numerical results demonstrate the remarkable long-time near conservation of the energies for the ERKN integrators and support our theoretical analysis presented in this paper.

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Bin Wang, Xinuan Wu. 2018-04-23. Long-time energy analysis of extended RKN integrators for muti-frequency highly oscillatory Hamiltonian systems. https://arxiv.org/abs/1804.08318

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