Abstract
Taking advantage of a previously developed method, which allows to map solutions of General Relativity into a broad family of theories of gravity based on the Ricci tensor (Ricci-based gravities), we find new exact analytical scalar field solutions by mapping the free-field static, spherically symmetric solution of General Relativity (GR) into quadratic f(R) gravity and the Eddington-inspired Born-Infeld gravity. The obtained solutions have some distinctive feature below the would-be Schwarzschild radius of a configuration with the same mass, though in this case no horizon is present. The compact objects found include wormholes, compact balls, shells of energy with no interior, and a new kind of object which acts as a kind of wormhole membrane. The latter object has Euclidean topology but connects antipodal points of its surface by transferring particles and null rays across its interior in virtually zero affine time. We point out the relevance of these results regarding the existence of compact scalar field objects beyond General Relativity that may effectively act as black hole mimickers.
Highlights
In the last few decades, the investigation of gravitating solutions supported by scalar fields has blossomed with the finding of unexpected and striking results
Taking advantage of a previously developed method, which allows to map solutions of General Relativity into a broad family of theories of gravity based on the Ricci tensor (Ricci-based gravities), we find new exact analytical scalar field solutions by mapping the free-field static, spherically symmetric solution of General Relativity (GR) into quadratic f (R) gravity and the Eddingtoninspired Born-Infeld gravity
In this work we have worked out and discussed exact analytical solutions for compact scalar field objects in two well motivated extensions of GR, namely, quadratic f (R) and Eddington-inspired Born-Infeld gravity, formulated in metric-affine spaces. These two models are particular examples of a large family of gravitational theories constructed in terms of scalars out of the Ricci tensor, and which admit an Einstein-frame representation of their field equations
Summary
In the last few decades, the investigation of gravitating solutions supported by scalar fields has blossomed with the finding of unexpected and striking results. The fact that existing numerical algorithms and codes are tightly attached to the struc- To overcome these difficulties, a novel approach to solve the field equations of modified theories of gravity formulated in metric-affine (or Palatini) spaces was recently introduced in [22] for general anisotropic fluids. A novel approach to solve the field equations of modified theories of gravity formulated in metric-affine (or Palatini) spaces was recently introduced in [22] for general anisotropic fluids The heart of this method lies on the existence of a duality between General Relativity (GR) coupled to some matter fields, described by a given Lagrangian density, and a family of theories built out of the (symmetrized) Ricci tensor and its contractions with the metric (dubbed Ricci-based gravity theories, or RBGs for short), coupled to the same kind of matter fields, but described by a different Lagrangian density. V we summarize our results and discuss some future avenues of research
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
