Modified gravity in the interior of population II stars

Abstract

We study the effects of a beyond-Horndeski theory of modified gravity in the interior of a population II star. We consider a simple phenomenological model of a $1.1M_{\odot }$ star that has left the main sequence, has a thin Hydrogen burning shell with a partially degenerate isothermal core, surrounded by a radiative envelope having two regions of distinct opacities. Using suitable matching conditions at the two internal boundaries, a numerical analysis of the resulting stellar equations in modified gravity is carried out. While overall, gravity may be weakened, resulting in a decrease of the luminosity and an increase of the radius of the star, these effects are reversed near the core. It is suggested how the model, within its limitations, can yield a bound on the modified gravity parameter.

arXiv comment13 pages, 3 figures

References in corpus (44)

• Modified Gravity and Cosmology
• The galileon as a local modification of gravity
• Comprehensive analytic formulae for stellar evolution as a function of mass and metallicity
• Chameleon Fields: Awaiting Surprises for Tests of Gravity in Space
• Chameleon Cosmology
• Generalized G-inflation: Inflation with the most general second-order field equations
• From k-essence to generalised Galileons
• Covariant Galileon
• Dark Energy after GW170817: dead ends and the road ahead
• Strong constraints on cosmological gravity from GW170817 and GRB 170817A
• Dark Energy after GW170817 and GRB170817A
• Implications of the Neutron Star Merger GW170817 for Cosmological Scalar-Tensor Theories
• Healthy theories beyond Horndeski
• Degenerate higher derivative theories beyond Horndeski: evading the Ostrogradski instability
• Transforming gravity: from derivative couplings to matter to second-order scalar-tensor theories beyond the Horndeski Lagrangian
• Exploring gravitational theories beyond Horndeski
• Testing General Relativity in Cosmology
• An introduction to the Vainshtein mechanism
• Cosmological Tests of Gravity
• Dark Energy and Modified Gravity in Degenerate Higher-Order Scalar-Tensor (DHOST) theories: a review
• Scalar-tensor theories and modified gravity in the wake of GW170817
• Stellar structure models in modified theories of gravity: lessons and challenges
• Dark energy in Horndeski theories after GW170817: A review
• Hamiltonian analysis of higher derivative scalar-tensor theories
• Breaking of Vainshtein screening in scalar-tensor theories beyond Horndeski
• Vainshtein mechanism after GW170817
• Relativistic Stars in Beyond Horndeski Theories
• Astrophysical Probes of the Vainshtein Mechanism: Stars and Galaxies
• Hydrogen Burning in Low Mass Stars Constrains Alternative Gravity Theories
• Modified gravity inside astrophysical bodies
• Testing Gravity Using Dwarf Stars
• Modified Gravity Makes Galaxies Brighter
• White Dwarf Critical Tests for Modified Gravity
• Celestial-Body Focused Dark Matter Annihilation Throughout the Galaxy
• Vainshtein regime in Scalar-Tensor gravity: constraints on DHOST theories
• Towards Strong Field Tests of Beyond Horndeski Gravity Theories
• White dwarfs and revelations
• Stellar Structure and Tests of Modified Gravity
• Minimum main sequence mass in quadratic Palatini $f(\mathcal{R})$ gravity
• Obtaining Precision Constraints on Modified Gravity with Helioseismology
• Early evolutionary tracks of low-mass stellar objects in modified gravity
• Lithium abundance is a gravitational model dependent quantity
• Constraining modified gravity from tidal phenomena in binary stars
• Dark Matter: Motivation, Candidates and Searches

Cited by in corpus (11)

• Stability criterion for white dwarfs in Palatini $f(R)$ gravity
• Fermi gas and modified gravity
• Metric-affine gravity effects on terrestrial (exo-)planets profiles
• Jupiter and jovian (exo)-planets in Palatini $f(\bar{R})$ gravity
• Giant planet formation in Palatini gravity
• Non-homogeneous exoplanets in metric-affine gravity
• Early evolution of fully convective stars in scalar-tensor gravity
• A stellar constraint on Eddington-inspired Born-Infeld gravity from cataclysmic variable binaries
• Cooling process of substellar objects in scalar-tensor gravity
• The Schönberg-Chandrasekhar limit in presence of small anisotropy and modified gravity
• Pre-main sequence evolution of low-mass stars in Eddington-inspired Born-Infeld gravity