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Modified gravity as a common cause for cosmic acceleration and flat galaxy rotation curves
Flat galaxy rotation curves and the accelerating Universe both imply the
existence of a critical acceleration, which is of the same order of magnitude
in both the cases, in spite of the galactic and cosmic length scales being
vastly different. Yet, it is customary to explain galactic acceleration by
invoking gravitationally bound dark matter, and cosmic acceleration by invoking
a `repulsive` dark energy. Instead, might it not be the case that the flatness
of rotation curves and the acceleration of the Universe have a common cause? In
this essay we propose a modified theory of gravity. By applying the theory on
galactic scales we demonstrate flat rotation curves without dark matter, and by
applying it on cosmological scales we demonstrate cosmic acceleration without
dark energy.Comment: 7 pages, 1 fgure. Honorable Mention in Gravity Research Foundation
Essay Contest 2012. v2: Two minor typos correcte
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