Homogeneous potentials, Lagrange's identity and Poisson geometry

A. V. Tsiganov

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arXiv · 2511.19903

Homogeneous potentials, Lagrange's identity and Poisson geometry

A. V. Tsiganov

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Abstract

The Lagrange identity expresses the second derivative of the moment of inertia of a system of material points through kinetic energy and homogeneous potential energy, from which follows the Jacobi well-known result on the instability of a system of gravitating bodies. In this work, it is proven that if a Hamiltonian system satisfies the Lagrange identity, then it possesses additional tensor invariants that are not expressed through the basic invariants existing for all Hamiltonian systems. A new class of Hamiltonian systems with inhomogeneous potentials is considered, which also possess similar additional tensor invariants.

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A. V. Tsiganov. 2025-11-25. Homogeneous potentials, Lagrange's identity and Poisson geometry. https://arxiv.org/abs/2511.19903

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