A reference for the covariant Hamiltonian boundary term
Abstract
The Hamiltonian for dynamic geometry generates the evolution of a spatial region along a vector field. It includes a boundary term which determines both the value of the Hamiltonian and the boundary conditions. The value gives the quasi-local quantities: energy-momentum, angular-momentum/center-of-mass. The boundary term depends not only on the dynamical variables but also on their reference values; the latter determine the ground state (having vanishing quasi-local quantities). For our preferred boundary term for Einstein's GR we propose 4D isometric matching and extremizing the energy to determine the reference metric and connection values.
Cite
@article{arxiv.1210.6148,
title = {A reference for the covariant Hamiltonian boundary term},
author = {James M. Nester and Chiang-Mei Chen and Jian-Liang Liu and Gang Sun},
journal= {arXiv preprint arXiv:1210.6148},
year = {2012}
}
Comments
submitted to the proceedings of the conference on Relativity and Gravitation: 100 Years after Einstein in Prague