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Dark matter candidate induced by Horndeski theory: dark matter halo and cosmological evolution

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 نشر من قبل Jiaming Shi
 تاريخ النشر 2019
  مجال البحث فيزياء
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We study spherically symmetric solutions with a scalar field in the shift-symmetric subclass of the Horndeski theory. Constructing an effective energy-momentum tensor of the scalar field based on the two-fluid model, we decompose the scalar field into two components: dark matter and dark energy.We find the dark-matter fluid is pressure-less, and its distribution of energy density obeys the inverse-square law. We show the scalar field dark matter can explain the galaxy rotation curve and discuss the time evolution of the dark matter in the cosmic background.



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