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Relativistic Lagrange Formulation

Robert Geroch·Gabriel Nagy·Oscar Reula
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Abstract

It is well-known that the equations for a simple fluid can be cast into what is called their Lagrange formulation. We introduce a notion of a generalized Lagrange formulation, which is applicable to a wide variety of systems of partial differential equations. These include numerous systems of physical interest, in particular, those for various material media in general relativity. There is proved a key theorem, to the effect that, if the original (Euler) system admits an initial-value formulation, then so does its generalized Lagrange formulation.

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Robert Geroch, Gabriel Nagy, Oscar Reula. 2001-02-14. Relativistic Lagrange Formulation. https://doi.org/10.1063/1.1364502

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