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arXiv · 1208.2525

Intrinsic time gravity and the Lichnerowicz-York equation

Niall Ó Murchadha·Chopin Soo·Hoi-Lai Yu
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Abstract

We investigate the effect on the Hamiltonian structure of general relativity of choosing an intrinsic time to fix the time slicing. 3-covariance with momentum constraint is maintained, but the Hamiltonian constraint is replaced by a dynamical equation for the trace of the momentum. This reveals a very simple structure with a local reduced Hamiltonian. The theory is easily generalised; in particular, the square of the Cotton-York tensor density can be added as an extra part of the potential while at the same time maintaining the classic 2 + 2 degrees of freedom. Initial data construction is simple in the extended theory; we get a generalised Lichnerowicz-York equation with nice existence and uniqueness properties. Adding standard matter fields is quite straightforward.

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Niall Ó Murchadha, Chopin Soo, Hoi-Lai Yu. 2012-08-13. Intrinsic time gravity and the Lichnerowicz-York equation. https://doi.org/10.1088/0264-9381/30/9/095016

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