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Inhomogeneous universes in observational coordinates

Roy Maartens·Neil Humphreys·David Matravers·Bill Stoeger
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Abstract

Isotropic inhomogeneous dust universes are analysed via observational coordinates based on the past light cones of the observer's galactic worldline. The field equations are reduced to a single first--order {\sc ode} in observational variables on the past light cone, completing the observational integration scheme. This leads naturally to an explicit exact solution which is locally nearly homogeneous (i.e. {\sc frw}), but at larger redshift develops inhomogeneity. New observational characterisations of homogeneity ({\sc frw} universes) are also given.

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Roy Maartens, Neil Humphreys, David Matravers, Bill Stoeger. 1995-11-15. Inhomogeneous universes in observational coordinates. https://doi.org/10.1088/0264-9381%2F13%2F6%2F030

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