https://doi.org/10.1140/epjc/s10052-020-8358-z
Regular Article - Theoretical Physics
Upper bounds on the compactness at the innermost light ring of anisotropic horizonless spheres
School of Mathematical Sciences, Qufu Normal University, Qufu, 273165, Shandong, China
* e-mail: yanpengphy@163.com
Received:
14
July
2020
Accepted:
14
August
2020
Published online:
19
August
2020
In the background of isotropic horizonless spheres, Hod recently provided an analytical proof of a bound on the compactness at the innermost light ring with the dominant energy condition. In this work, we extend the discussion of isotropic spheres to anisotropic spheres. With the dominant energy and non-negative trace conditions, we prove that Hod’s bound also holds in the case of anisotropic horizonless spheres.
© The Author(s), 2020