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arXiv · 0911.3852

Light-cone observations and cosmological models: implications for inhomogeneous models mimicking dark energy

Edward W. Kolb·Callum R. Lamb
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Abstract

Cosmological observables are used to construct cosmological models. Since cosmological observations are limited to the light cone, a fixed number of observables (even measured to arbitrary accuracy) may not uniquely determine a cosmological model without additional assumptions or considerations. A prescription for constructing a spherically symmetric, inhomogeneous cosmological model that exactly reproduces the luminosity-distance as a function of redshift and the light-cone mass density as a function of redshift of a $\Lambda$CDM model is employed to gain insight into how an inhomogeneous cosmological model might mimic dark energy models.

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Edward W. Kolb, Callum R. Lamb. 2009-11-19. Light-cone observations and cosmological models: implications for inhomogeneous models mimicking dark energy. https://arxiv.org/abs/0911.3852

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