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Lightcone reference for total gravitational energy

S. R. Lau
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Abstract

We give an explicit expression for gravitational energy, written solely in terms of physical spacetime geometry, which in suitable limits agrees with the total Arnowitt-Deser-Misner and Trautman-Bondi-Sachs energies for asymptotically flat spacetimes and with the Abbot-Deser energy for asymptotically anti-de Sitter spacetimes. Our expression is a boundary value of the standard gravitational Hamiltonian. Moreover, although it stands alone as such, we derive the expression by picking the zero-point of energy via a ``lightcone reference.''

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S. R. Lau. 1999-03-10. Lightcone reference for total gravitational energy. https://doi.org/10.1103/physrevd.60.104034

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