Andrzej Borowiec et al 1998 Class. Quantum Grav. 15 43 doi:10.1088/0264-9381/15/1/005
Andrzej Borowiec, Marco Ferraris, Mauro Francaviglia and Igor Volovich
Show affiliationsIt has been shown recently that, in the first-order (Palatini) formalism, there is universality of the Einstein equations and the Komar energy-momentum complex, 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 the Einstein equations and Komar's expression for the energy-momentum complex. In this paper a similar analysis (also within the framework of the first-order formalism) is performed for all nonlinear Lagrangians depending on the (symmetrized) Ricci square invariant. The main result is that the universality of the Einstein equations and Komar's energy-momentum complex also extends to this case (modulo a conformal transformation of the metric).
83C05 Einstein's equations (general structure, canonical formalism, Cauchy problems)
Issue 1 (January 1998)
Received 2 December 1997, in final form 30 June 1997
Andrzej Borowiec et al 1998 Class. Quantum Grav. 15 43
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