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arXiv · 0805.1312

A Method for Constructing a Lax Pair for the Ernst Equation

C. J. Papachristou·B. Kent Harrison
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Abstract

A systematic construction of a Lax pair and an infinite set of conservation laws for the Ernst equation is described. The matrix form of this equation is rewritten as a differential ideal of gl(2,R)-valued differential forms, and its symmetry condition is expressed as an exterior equation which is linear in the symmetry characteristic and has the form of a conservation law. By means of a recursive process, an infinite collection of such laws is then obtained, and the conserved "charges" are used to derive a linear exterior equation whose components constitute a Lax pair.

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C. J. Papachristou, B. Kent Harrison. 2008-05-09. A Method for Constructing a Lax Pair for the Ernst Equation. https://arxiv.org/abs/0805.1312

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