2017/06/30 by G. A. Carvalho, R. V. Lobato, P. H. R. S. Moraes +5
Earth and Planetary Sciences · Physics and Astronomy · #Black dwarf #Chandrasekhar limit #Cosmology and Gravitation Theories #Effective temperature #Geophysics and Gravity Measurements #Hydrostatic equilibrium #Massive compact halo object #Pulsars and Gravitational Waves Research #RADIUS #Stellar structure #Surface gravity #White dwarf #astro-ph.SR #gr-qc #hep-th #nucl-th
paper · pdf · doi:10.1140/epjc/s10052-017-5413-5
To be published in EPJC
openalex created_date 2017/06/23 · arxiv created 2017/11/24 · openalex publication_date 2017/12/01 · arxiv updated 2017/12/20 · openalex updated_date 2026/08/05
In this work we investigate the equilibrium configurations of white dwarfs in a modified gravity theory, namely, f(R, T) gravity, for which R and T stand for the Ricci scalar and trace of the energy-momentum tensor, respectively. Considering the functional form f(R,T)=R+2λ T , with λ being a constant, we obtain the hydrostatic equilibrium equation for the theory. Some physical properties of white dwarfs, such as: mass, radius, pressure and energy density, as well as their dependence on the parameter λ are derived. More massive and larger white dwarfs are found for negative values of λ when it decreases. The equilibrium configurations predict a maximum mass limit for white dwarfs slightly above the Chandrasekhar limit, with larger radii and lower central densities when compared to standard gravity outcomes. The most important effect of f(R, T) theory for massive white dwarfs is the increase of the radius in comparison with GR and also f(R) results. By comparing our results with some observational data of massive white dwarfs we also find a lower limit for λ , namely, λ >- 3× 10-4 .