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arXiv · 1904.10297

Necessary criterion of choosing the energy-momentum tensor and the Lagrange formalism

Yurii A. Spirichev
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Abstract

It is shown that the necessary criterion for choosing the energy-momentum tensor of a physical system is the form of its linear invariant, which should be the lagrangian of this physical system. Examples of energy-momentum tensors that meet this criterion are given. For an electromagnetic field in vacuum, the linear invariant of the energy-momentum tensor must be the canonical lagrangian or the quadratic invariant of the electromagnetic field tensor. A mathematical method for obtaining the lagrangian that complements the Lagrange formalism is proposed.

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Yurii A. Spirichev. 2019-04-19. Necessary criterion of choosing the energy-momentum tensor and the Lagrange formalism. https://arxiv.org/abs/1904.10297

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