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Milgroms Law and Lambdas Shadow: How Massive Gravity Connects Galactic and Cosmic Dynamics

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 نشر من قبل Sascha Trippe
 تاريخ النشر 2015
  مجال البحث فيزياء
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 تأليف Sascha Trippe




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Massive gravity provides a natural solution for the dark energy problem of cosmology and is also a candidate for resolving the dark matter problem. I demonstrate that, assuming reasonable scaling relations, massive gravity can provide for Milgroms law of gravity (or modified Newtonian dynamics) which is known to remove the need for particle dark matter from galactic dynamics. Milgroms law comes with a characteristic acceleration, Milgroms constant, which is observationally constrained to $a_0approx1.1times10^{-10}$ m/s$^2$. In the derivation presented here, this constant arises naturally from the cosmologically required mass of gravitons like $a_0propto csqrt{Lambda}propto c H_0sqrt{3Omega_{Lambda}}$, with $Lambda$, $H_0$, and $Omega_{Lambda}$ being the cosmological constant, the Hubble constant, and the third cosmological parameter, respectively. My derivation suggests that massive gravity could be the mechanism behind both, dark matter and dark energy.

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