Effects of Chameleon Scalar Field on Rotation Curves of the Galaxies

  title={Effects of Chameleon Scalar Field on Rotation Curves of the Galaxies},
  author={Piyabut Burikham and Sirachak Panpanich},
  journal={arXiv: High Energy Physics - Phenomenology},
We investigate the effects of chameleon scalar field to the effective density and pressure of a dark matter halo. The pressure is generated from the chameleonic fifth force on the matter. We demonstrate that the thick-shell non-singular boundary condition which forbids singular point leads to extremely stringent constraint on the matter-chameleon coupling when applied to galaxy. We argue that chameleon profile with central singularity is more likely to develop in general physical situation. The… 

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