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Observability of spherical photon orbits in near-extremal Kerr black holes

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 نشر من قبل Takahisa Igata
 تاريخ النشر 2019
  مجال البحث فيزياء
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We investigate the spherical photon orbits in near-extremal Kerr spacetimes. We show that the spherical photon orbits with impact parameters in a finite range converge on the event horizon. Furthermore, we demonstrate that the Weyl curvature near the horizon does not generate the shear of a congruence of such light rays. Because of this property, a series of images produced by the light orbiting around a near-extremal Kerr black hole several times can be observable.



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