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arXiv · 2412.02633

Dirac bracket and Nambu structures

J. Antonio García·Rafael Cruz-Alvarez
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Abstract

A relation between the Dirac bracket (DB) and Nambu bracket (NB) is presented. The Nambu bracket can be related with Dirac bracket if we can write the DB as a generalized Poisson structure. The NB associated with DB have all the standard properties of the original DB. When the dimension of the phase space is $s+2$ where $s$ is the number of second class constraints, the associated Nambu structure has $s+2$ entries and reduces to the Dirac bracket when $s$ of its entries are fixed to be the second class constraints. In general, when the dimension of phase space is $d=r+s$ a new Nambu structure that describes correctly the constrained dynamics can also be constructed but in thsi case addicional conditidionts are requiered. In that case the associated NB corresponds to a ``Dirac-Nambu'' bracket with $r$ entries.

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J. Antonio García, Rafael Cruz-Alvarez. 2024-12-03. Dirac bracket and Nambu structures. https://arxiv.org/abs/2412.02633

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