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arXiv · gr-qc/9407004

A Quadratic Spinor Lagrangian for General Relativity

James M. Nester·Roh Suan Tung
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Abstract

We present a new finite action for Einstein gravity in which the Lagrangian is quadratic in the covariant derivative of a spinor field. Via a new spinor-curvature identity, it is related to the standard Einstein-Hilbert Lagrangian by a total differential term. The corresponding Hamiltonian, like the one associated with the Witten positive energy proof is fully four-covariant. It defines quasi-local energy-momentum and can be reduced to the one in our recent positive energy proof. (Fourth Prize, 1994 Gravity Research Foundation Essay.)

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James M. Nester, Roh Suan Tung. 1994-07-06. A Quadratic Spinor Lagrangian for General Relativity. https://doi.org/10.1007/bf02107951

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