Numerical Approach to the Exterior Solution of Spherically Symmetric and Static Configuration in Scalar-Tensor Theories

Abstract

We numerically examine the exterior solution of spherically symmetric and static configuration in scalar-tensor theories by using the nonminimally coupled scalar field with zero potential as our sample model. Our main purpose in this work is to fit the resulting data of the numerical solutions in the interested region by seeking for approximate analytical expressions which are weakly dependent of the parameters of a model, such as the nonminimal coupling constant in the present case. To this end, we determine the main forms of the mass and the metric functions in terms of the scalar field and their surface values. Then, we provide a function for the scalar field that contains only the mass and the radius of the configuration together with the surface and the asymptotic values of the scalar field. Therefore, we show that the exterior solution can be expressed in a form which does not depend on the parameters of a chosen model up to an order of accuracy around $10^{-5}$.

arXiv comment18 pages, 8 figures

References in corpus (27)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• The Confrontation between General Relativity and Experiment
• A unified equation of state of dense matter and neutron star structure
• Equations of state for supernovae and compact stars
• The Nuclear Equation of State and Neutron Star Masses
• From hadrons to quarks in neutron stars: a review
• The relativistic pulsar-white dwarf binary PSR J1738+0333 II. The most stringent test of scalar-tensor gravity
• Relativistic Mean-Field Theory and the High-Density Nuclear Equation of State
• Probes and Tests of Strong-Field Gravity with Observations in the Electromagnetic Spectrum
• Analytical representations of unified equations of state for neutron-star matter
• Stellar structure models in modified theories of gravity: lessons and challenges
• Neutron stars in scalar-tensor theories of gravity and catastrophe theory
• Constraining nonperturbative strong-field effects in scalar-tensor gravity by combining pulsar timing and laser-interferometer gravitational-wave detectors
• On spontaneous scalarization
• Towards New Tests of Strong-field Gravity with Measurements of Surface Atomic Line Redshifts from Neutron Stars
• Exact dark energy star solutions
• What does a measurement of mass and/or radius of a neutron star constrain: Equation of state or gravity?
• Semi-Analytic Stellar Structure in Scalar-Tensor Gravity
• Impact of the equation-of-state -- gravity degeneracy on constraining the nuclear symmetry energy from astrophysical observables
• Neutron star pulse profiles in scalar-tensor theories of gravity
• Universal Relations and Alternative Gravity Theories
• Neutron Star Structure in the Presence of Nonminimally Coupled Scalar Fields
• Degeneracy in Studying the Supranuclear Equation of State and Modified Gravity with Neutron Stars
• Particlelike distributions of the Higgs field nonminimally coupled to gravity
• Compactness of neutron stars and Tolman VII solutions in scalar-tensor gravity
• The exterior spacetime of relativistic stars in scalar-Gauss-Bonnet gravity
• A Neutron Star with a Strange Quark Star-like Mass-Radius Relation