On the energy-momentum density of gravitational plane waves

Abstract

By embedding Einstein's original formulation of general relativity into a broader context, we show that a dynamic covariant description of gravitational stress-energy emerges naturally from a variational principle. A tensor T-G is constructed from a contraction of the Bel tensor with a symmetric covariant second degree tensor field (P and has a form analogous to the stress-energy tensor of the Maxwell field in an arbitrary spacetime. For plane-fronted gravitational waves helicity-2 polarized (graviton) states can be identified carrying non-zero energy and momentum.