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arXiv · 0707.3454

Solving Linearized Equations of the $N$-body Problem Using the Lie-integration Method

Andras Pal·Aron Suli
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Abstract

Several integration schemes exits to solve the equations of motion of the $N$-body problem. The Lie-integration method is based on the idea to solve ordinary differential equations with Lie-series. In the 1980s this method was applied for the $N$-body problem by giving the recurrence formula for the calculation of the Lie-terms. The aim of this works is to present the recurrence formulae for the linearized equations of motion of $N$-body systems. We prove a lemma which greatly simplifies the derivation of the recurrence formulae for the linearized equations if the recurrence formulae for the equations of motions are known. The Lie-integrator is compared with other well-known methods. The optimal step size and order of the Lie-integrator are calculated. It is shown that a fine-tuned Lie-integrator can be 30%-40% faster than other integration methods.

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Andras Pal, Aron Suli. 2007-07-23. Solving Linearized Equations of the $N$-body Problem Using the Lie-integration Method. https://doi.org/10.1111/j.1365-2966.2007.12248.x

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