Lemaitre-Tolman-Bondi Static Universe in Rastall-like Gravity

Understand

In this work, we try to obtain a stable Lemaitre-Tolman-Bondi (LTB) static universe, which is spherically symmetric and radially inhomogeneous.

• However, this is not an easy task, and fails in general relativity (GR) and various modified gravity theories, because the corresponding LTB static universes must reduce to the Friedmann-Robertson-Walker (FRW) static universes.
• We find a way out in a new type of modified gravity theory, in which the conservation of energy and momentum is broken.
• In this work, we have proposed a novel modification to the original Rastall gravity.