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Galaxy Bulges As Tests of CDM vs MOND in Strong Gravity

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 نشر من قبل HongSheng Zhao
 تاريخ النشر 2008
  مجال البحث فيزياء
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 تأليف HongSheng Zhao




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The tight correlation between galaxy bulges and their central black hole masses likely emerges in a phase of rapid collapse and starburst at high redshift, due to the balance of gravity on gas with the feedback force from starbursts and the wind from the black hole; the average gravity on per unit mass of gas is ~ 2 x 10^-10 m/sec^2 during the star burst phase. This level of gravity could come from the real r^{-1} cusps of Cold Dark Matter (CDM) halos, but the predicted gravity would have a large scatter due to dependence on cosmological parameters and formation histories. Better agreement is found with the gravity from the scalar field in some co-varia



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