We consider light propagation in an inhomogeneous irrotational dust universewith vanishing cosmological constant, with initial conditions as in standardlinear perturbation theory. A non-perturbative approach to the dynamics of sucha universe is combined with a distance formula based on the Sachs opticalequations. Then a numerical study implies a redshift-distance relation thatroughly agrees with observations. Interpreted in the standard homogeneoussetup, our results would appear to imply the currently accepted values for theHubble rate and the deceleration parameter; furthermore there is consistencywith density perturbations at last scattering. The determination of these threequantities relies only on a single parameter related to a cutoff scale.Discrepancies with the existing literature are related to subtleties of higherorder perturbation theory which make both the reliability of the presentapproach and the magnitude of perturbative effects beyond second order hard toassess.
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