On the Area Distance and the Riemannian Geometry
نویسنده
چکیده
In the standard cosmological model, one usually deals with the RobertsonWalker line element to describe various kinematical, dynamical or alchemical processes in the Universe. Although the observations refer to the high degree of homogeneity and isotropy of the Universe, current and future measurements would require theoretical models with a more general geometry of spacetime. A fundamental role in all kinds of astronomical observation plays area, luminosity, angular diameter or comoving distances. In this paper we choose an area distance to investigate its dependence on the parameters of the Riemannian geometry. We start with the definition of the area(corrected luminosity) distance due to Kristian and Sachs [1] :
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