Matter Seen at Many Scales and the Geometry of Averaging in Relativistic Cosmology
نویسندگان
چکیده
We investigate the scale–dependence of Eulerian volume averages of scalar functions on Riemannian three–manifolds. We propose a complementary view of a Lagrangian scaling of variables as opposed to their Eulerian averaging on spatial domains. This program explains rigorously the origin of the Ricci deformation flow for the metric, a flow which, on heuristic grounds, has been already suggested as a possible candidate for averaging the initial data set for cosmological spacetimes. email: [email protected] email: [email protected]
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تاریخ انتشار 2001