2021/05/11 by J. Soldateschi, N. Bucciantini, Soldateschi, Jacopo +3
Earth and Planetary Sciences · Physics and Astronomy · #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #Geophysics and Gravity Measurements #High Energy Astrophysical Phenomena (astro-ph.HE) #Pulsars and Gravitational Waves Research #Solar and Space Plasma Dynamics
paper · pdf · doi:10.48550/arxiv.2105.04889
openalex publication_date 2021/05/11 · openalex created_date 2022/07/25 · openalex updated_date 2026/07/28
General relativity probably is not the definitive theory of gravity, due a number or issues, both from the theoretical and from the observational point of view. Alternative theories of gravity were conceived to extend general relativity and account for such issues. Among the most promising ones are scalar-tensor theories, which predict an enrichment of the phenomenology of compact objects, like neutron stars. We updated the well-tested XNS code to numerically solve the Einstein-Maxwell equations for a stationary, magnetised neutron star in a class of scalar-tensor theories containing the spontaneous scalarisation phenomenon. We found that there exist "quasi-universal relations" among the mass, radius, scalar charge and magnetic deformation of a neutron star that are true independently of the equation of state, both in general relativity and in scalar-tensor theories. This result could potentially provide new tools to test scalar-tensor theories and the magnetic field geometry inside neutron stars.