Generalization of Hamiltonian Mechanics to a Three Dimensional Phase Space

TL;DR

This paper extends classical Hamiltonian mechanics to a three-dimensional phase space by introducing a symplectic 3-form and a generalized Poisson bracket, preserving key properties like volume invariance and establishing a new geometric framework.

Contribution

It proposes a novel generalization of Hamiltonian mechanics to 3D phase space, replacing the symplectic 2-form with a 3-form and analyzing its implications.

Findings

Existence of local coordinates with constant symplectic 3-form components

Preservation of volume element in the generalized phase space

Jacobi identity corresponds to the closure of the symplectic 3-form

Abstract

Classical Hamiltonian mechanics is realized by the action of a Poisson bracket on a Hamiltonian function. The Hamiltonian function is a constant of motion (the energy) of the system. The properties of the Poisson bracket are encapsulated in the symplectic 2-form, a closed second order differential form. Due to closure, the symplectic 2-form is preserved by the Hamiltonian flow, and it assigns an invariant (Liouville) measure on the phase space through the Lie-Darboux theorem. In this paper we propose a generalization of classical Hamiltonian mechanics to a three-dimensional phase space: the classical Poisson bracket is replaced with a generalized Poisson bracket acting on a pair of Hamiltonian functions, while the symplectic 2-form is replaced by a symplectic 3-form. We show that, using the closure of the symplectic 3-form, a result analogous to the classical Lie-Darboux theorem holds: locally, there exist smooth coordinates such that the components of the symplectic 3-form are constants, and the phase space is endowed with a preserved volume element. Furthermore, as in the classical theory, the Jacobi identity for the generalized Poisson bracket mathematically expresses the closure of the associated symplectic form. As a consequence, constant skew-symmetric third order contravariant tensors always define generalized Poisson brackets. This is in contrast with generalizations of Hamiltonian mechanics postulating the fundamental identity as replacement for the Jacobi identity. In particular, we find that the fundamental identity represents a stronger requirement than the closure of the symplectic 3-form.