Ellipticity weakens chameleon screening

  title={Ellipticity weakens chameleon screening},
  author={Clare Burrage and Edmund J. Copeland and James A. Stevenson},
  journal={Physical Review D},
The chameleon mechanism enables a long-range fifth force to be screened in dense environments when nontrivial self-interactions of the field cause its mass to increase with the local density. To date, chameleon fifth forces have mainly been studied for spherically symmetric sources; however, the nonlinear self-interactions mean that the chameleon responds to changes in the shape of the source differently to gravity. In this work we focus on ellipsoidal departures from spherical symmetry and… 

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