On-shell Lagrangians as total derivatives and the generalized Komar charge

José Luis V. Cerdeira; Tomás Ortín

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arXiv · 2506.14024

On-shell Lagrangians as total derivatives and the generalized Komar charge

José Luis V. Cerdeira·Tomás Ortín

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Abstract

Lagrangians which transform homogeneously under a global transformation of the fields (a global rescaling, for instance) can be written on-shell as a total derivative which has a universal, solution-independent expression, using a functional version of the Euler theorem for homogeneous functions. We study the uniqueness of this expression and how this result can be used in the construction of generalized Komar charges.

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José Luis V. Cerdeira, Tomás Ortín. 2025-06-16. On-shell Lagrangians as total derivatives and the generalized Komar charge. https://arxiv.org/abs/2506.14024

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