General Relativity: An Introduction for Physicists · Problem 17.3

Linearised general relativity — Hobson, Efstathiou & Lasenby

Physics · linearised-riemann-ricci-einstein-equations

Problem

If gμν=ημν+hμνg_{\mu\nu} = \eta_{\mu\nu} + h_{\mu\nu} with ∣hμν∣≪1|h_{\mu\nu}| \ll 1, verify that, to first order in hμνh_{\mu\nu}, Rσμνρ=12(∂ν∂μhρσ+∂ρ∂σhμν−∂ν∂σhμρ−∂ρ∂μhνσ),R^{\sigma}{}_{\mu\nu\rho} = \tfrac{1}{2}(\partial_{\nu}\partial_{\mu}h^{\sigma}_{\rho} + \partial_{\rho}\partial^{\sigma}h_{\mu\nu} - \partial_{\nu}\partial^{\sigma}h_{\mu\rho} - \partial_{\rho}\partial_{\mu}h^{\sigma}_{\nu}), Rμν=12(∂ν∂μh+□2hμν−∂ν∂ρhμρ−∂ρ∂μhνρ),R_{\mu\nu} = \tfrac{1}{2}(\partial_{\nu}\partial_{\mu}h + \Box^2 h_{\mu\nu} - \partial_{\nu}\partial_{\rho}h^{\rho}_{\mu} - \partial_{\rho}\partial_{\mu}h^{\rho}_{\nu}), R=□2h−∂ρ∂μhμρ.R = \Box^2 h - \partial_{\rho}\partial_{\mu}h^{\mu\rho}. Hence show that the linearised Einstein field equations are given by ∂ν∂μh+□2hμν−∂ν∂ρhμρ−∂ρ∂μhνρ−ημν(□2h−∂ρ∂σhσρ)=−2κTμν.\partial_{\nu}\partial_{\mu}h + \Box^2 h_{\mu\nu} - \partial_{\nu}\partial_{\rho}h^{\rho}_{\mu} - \partial_{\rho}\partial_{\mu}h^{\rho}_{\nu} - \eta_{\mu\nu}(\Box^2 h - \partial_{\rho}\partial_{\sigma}h^{\sigma\rho}) = -2\kappa T_{\mu\nu}.

Related theory

Browse the problem library