Impact of the Rastall parameter on perfect fluid spheres

Understand

We examine the effects of the Rastall parameter on the behaviour of spherically symmetric static distributions of perfect fluid matter.

• It was claimed by Visser [Physics Letters B, 782, 83, (2018)] that the Rastall proposition is completely equivalent to the Einstein theory.
• While many authors have raised contrary arguments, our intention is to analyze the properties of Rastall gravity through variation of the Rastall parameter in the context of perfect fluids spheres that may be used to model neutron stars or cold fluid planets.
• This analysis also serves to counter the claim that Rastall gravity is equivalent to the standard Einstein theory.