182 citations · 1.4k across the 52 of their papers we have counts for
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Quasilocal Energy-Momentum for Geometric Gravity Theories
Chiang-Mei Chen, James M. Nester, Roh Suan Tung
From a covariant Hamiltonian formulation, using symplectic ideas, we obtain covariant quasilocal energy-momentum boundary expressions for general gravity theories. The expressions…
A Quadratic Spinor Lagrangian for General Relativity
James M. Nester, Roh Suan Tung
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 r…
Some Spinor-Curvature Identities
James M. Nester, Roh Suan Tung, Vadim V. Zhytnikov
We describe a class of spinor-curvature identities which exist for Riemannian or Riemann-Cartan geometries. Each identity relates an expression quadratic in the covariant derivativ…
Ashtekar's New Variables and Positive Energy
James M. Nester, Roh-Suan Tung, Yuan Zhong Zhang
We discuss earlier unsuccessful attempts to formulate a positive gravitational energy proof in terms of the New Variables of Ashtekar. We also point out the difficulties of a Witte…