Chandrasekhar Mass Limit of White Dwarfs in Modified Gravity
read the original abstract
We investigate the Chandrasekhar mass limit for white dwarfs in various models of $f(R)$ gravity. Two equations of state for stellar matter are used: simple relativistic polytropic equation with polytropic index $n=3$ and the realistic Chandrasekhar equation of state. For calculations it is convenient to use the equivalent scalar-tensor theory in the Einstein frame and then to return in the Jordan frame picture. For white dwarfs we can neglect terms containing relativistic effects from General Relativity and we consider the reduced system of equations. Its solution for any model of $f(R)=R+\beta R^{m}$ ($m\geq 2$, $\beta>0$) gravity leads to the conclusion that the stellar mass decreases in comparison with standard General Relativity. For realistic equations of state we find that there is a value of the central density for which the mass of white dwarf peaks. Therefore, in frames of modified gravity there is lower limit on the radius of stable white dwarfs and this minimal radius is greater than in General Relativity.
This paper has not been read by Pith yet.
Forward citations
Cited by 2 Pith papers
-
$\phi$-Dwarfs: White Dwarfs probe Quadratically Coupled Scalars
White dwarf mass-radius data exclude large parameter space for ultralight scalars quadratically coupled to fermions by predicting forbidden radius gaps and mass shifts toward the Chandrasekhar limit or altered maximum masses.
-
Impact of the SNe Ia Magnitude Transition at 20 Mpc on Cosmological Parameter Estimation
A 0.19 mag step in supernova absolute magnitude at 20 Mpc improves data fit and increases the Hubble constant by 2% while leaving matter density and dark energy parameters stable.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.