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Spherically symmetric solutions of Einstein + non-polynomial gravities

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 نشر من قبل Bahtiyar Ozgur Sarioglu
 تاريخ النشر 2007
  مجال البحث فيزياء
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We obtain the static spherically symmetric solutions of a class of gravitational models whose additions to the General Relativity (GR) action forbid Ricci-flat, in particular, Schwarzschild geometries. These theories are selected to maintain the (first) derivative order of the Einstein equations in Schwarzschild gauge. Generically, the solutions exhibit both horizons and a singularity at the origin, except for one model that forbids spherical symmetry altogether. Extensions to arbitrary dimension with a cosmological constant, Maxwell source and Gauss-Bonnet terms are also considered.



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