Unattainable extended spacetime regions in conformal gravity

  • Hrishikesh Chakrabarty
  • Carlos A. Benavides-Gallego
  • Cosimo BambiEmail author
  • Leonardo Modesto
Open Access
Regular Article - Theoretical Physics


The Janis-Newman-Winicour metric is a solution of Einstein’s gravity minimally coupled to a real massless scalar field. The γ-metric is instead a vacuum solution of Einstein’s gravity. Both spacetimes have no horizon and possess a naked singularity at a finite value of the radial coordinate, where curvature invariants diverge and the spacetimes are geodetically incomplete. In this paper, we reconsider these solutions in the framework of conformal gravity and we show that it is possible to solve the spacetime singularities with a suitable choice of the conformal factor. Now curvature invariants remain finite over the whole spacetime. Massive particles never reach the previous singular surface and massless particles can never do it with a finite value of their affine parameter. Our results support the conjecture according to which conformal gravity can fix the singularity problem that plagues Einstein’s gravity.


Classical Theories of Gravity Spacetime Singularities 


Open Access

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Copyright information

© The Author(s) 2018

Authors and Affiliations

  • Hrishikesh Chakrabarty
    • 1
  • Carlos A. Benavides-Gallego
    • 1
  • Cosimo Bambi
    • 1
    • 2
    Email author
  • Leonardo Modesto
    • 3
  1. 1.Center for Field Theory and Particle Physics and Department of PhysicsFudan UniversityShanghaiChina
  2. 2.Theoretical AstrophysicsEberhard-Karls Universität TübingenTübingenGermany
  3. 3.Department of PhysicsSouthern University of Science and Technology (SUSTech)ShenzhenChina

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