Wormhole geometries induced by action-dependent Lagrangian theories
Abstract
In this work, we explore wormhole geometries in a recently proposed modified gravity theory arising from a nonconservative gravitational theory, tentatively denoted action-dependent Lagrangian theories. The generalized gravitational field equation essentially depends on a background four-vector λμ, that plays the role of a coupling parameter associated with the dependence of the gravitational Lagrangian upon the action, and may generically depend on the spacetime coordinates. Considering wormhole configurations, by using "Buchdahl coordinates," we find that the four-vector is given by λμ=(0 ,0 ,λθ,0 ) and that the spacetime geometry is severely restricted by the condition gt tgu u=-1 , where u is the radial coordinate. We find a plethora of specific asymptotically flat, symmetric, and asymmetric solutions with power law choices for the function λ , by generalizing the Ellis-Bronnikov solutions and the recently proposed black-bounce geometries, among others. We show that these compact objects possess a far richer geometrical structure than their general relativistic counterparts.
- Publication:
-
Physical Review D
- Pub Date:
- February 2021
- DOI:
- 10.1103/PhysRevD.103.044018
- arXiv:
- arXiv:2012.00047
- Bibcode:
- 2021PhRvD.103d4018A
- Keywords:
-
- General Relativity and Quantum Cosmology;
- Astrophysics - High Energy Astrophysical Phenomena;
- High Energy Physics - Theory
- E-Print:
- 11 pages, 5 figures, V2: version accepted for publication in PRD