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Updated: Jul 17, 2026

Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Can cosmic structure form without dark matter?
Scott Dodelson1, Michele Liguori
1Particle Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, Illinois 60510-0500, USA.
Abstract:
One of the prime pieces of evidence for dark matter is the observation of large overdense regions in the Universe. To account for this observation, perturbations had to have grown since recombination by a factor greater than (1+z*) approximately 1180 where z* is the epoch of recombination. This enhanced growth does not happen in general relativity, and so dark matter is needed in the standard theory. We show here that enhanced growth can occur in alternatives to general relativity, in particular, in Bekenstein's relativistic version of modified Newtonian dynamics.
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