English

Noether currents and generators of local gauge transformations in the covariant canonical formalism

General Relativity and Quantum Cosmology 2023-07-06 v3 High Energy Physics - Theory Mathematical Physics math.MP

Abstract

We investigate generators of local transformations in the covariant canonical formalism (CCF). The CCF treats space and time on an equal footing regarding the differential forms as the basic variables. The conjugate forms πA\pi_A are defined as derivatives of the Lagrangian dd-form L(ψA,dψA)L(\psi^A, d\psi^A) with respect to dψAd\psi^A, namely πA:=L/dψA\pi_A := \partial L/\partial d\psi^A, where ψA\psi^A are pp-form dynamical fields. The form-canonical equations are derived from the form-Legendre transformation of the Lagrangian form H:=dψAπALH:=d\psi^A \wedge \pi_A - L. We show that the Noether current form is the generator of an infinitesimal transformation ψAψA+δψA\psi^A \to \psi^A + \delta \psi^A if the transformation of the Lagrangian form is given by δL=dl\delta L=dl and δψA\delta \psi^A and ll depend on only ψA\psi^A and the parameters. As an instance, we study the local gauge transformation for the gauge field and the local Lorentz transformation for the second order formalism of gravity.

Keywords

Cite

@article{arxiv.2201.06102,
  title  = {Noether currents and generators of local gauge transformations in the covariant canonical formalism},
  author = {Satoshi Nakajima},
  journal= {arXiv preprint arXiv:2201.06102},
  year   = {2023}
}

Comments

9 pages, no figure. arXiv admin note: substantial text overlap with arXiv:1909.06779