On the number of light rings in curved spacetimes of ultra-compact objects

In a very interesting paper, Cunha, Berti, and Herdeiro have recently claimed that ultra-compact objects, self-gravitating horizonless solutions of the Einstein field equations which have a light ring, must possess at least two (and, in general, an even number of) light rings, of which the inner one...

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Bibliographic Details
Main Author: Shahar Hod
Format: Article
Language:English
Published: Elsevier 2018-01-01
Series:Physics Letters B
Online Access:http://www.sciencedirect.com/science/article/pii/S0370269317309139