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arXiv · 2104.03609

On the Carath\'eodory form in higher-order variational field theory

Zbyněk Urban·Jana Volná
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Abstract

The Carath\'eodory form of the calculus of variations belongs to the class of Lepage equivalents of first-order Lagrangians in field theory. Here, this equivalent is generalized for second- and higher-order Lagrangians by means of intrisic geometric operations applied to the well-known Poincar\'e--Cartan form and principal component of Lepage forms, respectively. For second-order theory, our definition coincides with the previous result obtained by Crampin and Saunders in a different way. The Carath\'eodory equivalent of the Hilbert Lagrangian in general relativity is discussed.

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Zbyněk Urban, Jana Volná. 2021-04-08. On the Carath\'eodory form in higher-order variational field theory. https://arxiv.org/abs/2104.03609

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