ENERGY-MOMENTUM COMPLEX FOR NONLINEAR GRAVITATIONAL LAGRANGIANS IN THE 1ST-ORDER FORMALISM

It has been recently shown that there is universality of Einstein equations, in the first-order (Palatini) formalism, in the sense that for a generic nonlinear Lagrangian depending only on the scalar curvature of a metric and a torsionless connection one always gets Einstein equations. In this paper the energy-density flow for nonlinear gravitational Lagrangians is investigated in this formalism. It is shown that in the generic case the energy-momentum complex does not depend on the Lagrangian and is in fact equal to the Komar complex, known in the purely metric formalism for the standard linear Hilbert Lagrangian.