Shadows of spherically symmetric black holes and naked singularities

  title={Shadows of spherically symmetric black holes and naked singularities},
  author={Rajibul Shaikh and Prashant Kocherlakota and Ramesh Narayan and Pankaj S. Joshi},
  journal={Monthly Notices of the Royal Astronomical Society},
We compare shadows cast by Schwarzschild black holes with those produced by two classes of naked singularities that result from gravitational collapse of spherically symmetric matter. The latter models consist of an interior naked singularity space–time restricted to radii r ≤ R_b, matched to Schwarzschild space–time outside the boundary radius R_b. While a black hole always has a photon sphere and always casts a shadow, we find that the naked singularity models have photon spheres only if a… 

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