General class of wormhole geometries in conformal Weyl gravity

Lobo, Francisco S. N.

doi:10.48550/arxiv.0801.4401

Cited by 14 publications

(30 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the original papers by Mannheim and Kazanas ([13], [14]), and in the CG wormhole analysis by F. Lobo [28], the computation of the non-zero components of W µν was done indirectly by differentiating the Weyl action I W and using Bianchi and trace identities. In contrast, in this work, we compute all the relevant tensors directly from their definitions, using a specialized Mathematica program, which was developed by one of us for a previous study of the warp drive in CG [24].…”

Section: Conformal Gravity and The Stress-energy Tensormentioning

confidence: 99%

“…Continuing along this line of investigation, the main objective of this paper is to apply CG to traversable wormhole geometries and analyze the related energy conditions and other characteristics of the resultant solutions. Some work on the subject already exists in the literature ( [28], [29]), showing that in some cases the energy conditions are not violated. We propose to find more general wormhole solutions, which do not violate the energy conditions in CG, at least in the vicinity of the wormhole throat.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Wormhole geometries in fourth-order conformal Weyl gravity

Varieschi

Ault

2016

Int. J. Mod. Phys. D

View full text Add to dashboard Cite

We present an analysis of the classic wormhole geometries based on conformal Weyl gravity, rather than standard general relativity. The main characteristics of the resulting traversable wormholes remain the same as in the seminal study by Morris and Thorne, namely, that effective super-luminal motion is a viable consequence of the metric.Improving on previous work on the subject, we show that for particular choices of the shape and redshift functions the wormhole metric in the context of conformal gravity does not violate the main energy conditions at or near the wormhole throat.Some exotic matter might still be needed at the junction between our solutions and flat spacetime, but we demonstrate that the averaged null energy condition (as evaluated along radial null geodesics) is satisfied for a particular set of wormhole geometries.Therefore, if fourth-order conformal Weyl gravity is a correct extension of general relativity, traversable wormholes might become a realistic solution for interstellar travel.

show abstract

Section: Conformal Gravity and The Stress-energy Tensormentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Wormhole geometries in fourth-order conformal Weyl gravity

Varieschi

Ault

2016

Int. J. Mod. Phys. D

View full text Add to dashboard Cite

show abstract

“…1 for adjusted values of the free parameters. The quantity ρ + p r turns negative at r/M = 2 which is precisely 11 10 r 0 for r 0 /M = 2 10 11 = 1.90693. The interior solution should at most stop there.…”

Section: Wormhole Solutions In the Neighborhood Of The Throatmentioning

confidence: 94%

“…Matter that violates the NEC is denoted as exotic matter. Wormhole solutions have been also found in other theories, see, e.g., [4][5][6][7][8][9][10][11][12][13] and [14] for reviews. In these works the NEC for the matter is also violated.…”

Section: Introductionmentioning

confidence: 90%

Wormholes in generalized hybrid metric-Palatini gravity obeying the matter null energy condition everywhere

2018

View full text Add to dashboard Cite

Wormhole solutions in a generalized hybrid metric-Palatini matter theory, given by a gravitational Lagrangian f (R, R), where R is the metric Ricci scalar, and R is a Palatini scalar curvature defined in terms of an independent connection, and a matter Lagrangian, are found. The solutions are worked in the scalar-tensor representation of the theory, where the Palatini field is traded for two scalars, ϕ and ψ, and the gravitational term R is maintained. The main interest in the solutions found is that the matter field obeys the null energy condition (NEC) everywhere, including the throat and up to infinity, so that there is no need for exotic matter. The wormhole geometry with its flaring out at the throat is supported by the higher-order curvature terms, or equivalently, by the two fundamental scalar fields, which either way can be interpreted as a gravitational fluid. Thus, in this theory, in building a wormhole, it is possible to exchange the exoticity of matter by the exoticity of the gravitational sector. The specific wormhole displayed, built to obey the matter NEC from the throat to infinity, has three regions, namely, an interior region containing the throat, a thin shell of matter, and a vacuum Schwarzschild anti-de Sitter (AdS) exterior. For hybrid metric-Palatini matter theories this wormhole solution is the first where the NEC for the matter is verified for the entire spacetime keeping the solution under asymptotic control. The existence of this type of solutions is in line with the idea that traversable wormholes bore by additional fundamental gravitational fields, here disguised as scalar fields, can be found without exotic matter. Concomitantly, the somewhat concocted architecture needed to assemble a complete wormhole solution for the whole spacetime may imply that in this class of theories such solutions are scarce. arXiv:1808.08975v1 [gr-qc]

show abstract

“…Early work dates from the late 1980s [8][9][10][11][12][13][14]. Lorentzian wormholes became considerably more mainstream in the 1990s , including work on energy condition violations [36][37][38][39][40][41][42], with significant work continuing into the decades 2000-2009 [43][44][45][46][47][48][49][50][51][52][53][54][55][56] and 2010-2019 [57][58][59][60][61][62][63][64][65][66][67][68][69][70]. We shall particularly focus on the thin-shell formalism [71][72][73][74][75][76], first applied to Lorentzian wormholes in [10,…”

mentioning

confidence: 99%

Dynamic thin-shell black-bounce traversable wormholes

Lobo,

Simpson,

Visser

2020

Preprint

Self Cite

View full text Add to dashboard Cite

Based on the recently introduced black-bounce spacetimes, we shall consider the construction of the related spherically symmetric thin-shell traversable wormholes within the context of standard general relativity. All of the really unusual physics is encoded in one simple parameter a which characterizes the scale of the bounce. Keeping the discussion as close as possible to standard general relativity is the theorist's version of only adjusting one feature of the model at a time. We shall modify the standard thin-shell traversable wormhole construction, each bulk region now being a black-bounce spacetime, and with the physics of the thin shell being (as much as possible) derivable from the Einstein equations. Furthermore, we shall apply a dynamical analysis to the throat by considering linearized radial perturbations around static solutions, and demonstrate that the stability of the wormhole is equivalent to choosing suitable properties for the exotic material residing on the wormhole throat. The construction is sufficiently novel to be interesting, and sufficiently straightforward to be tractable.

show abstract

General class of wormhole geometries in conformal Weyl gravity

Cited by 14 publications

References 0 publications

Wormhole geometries in fourth-order conformal Weyl gravity

Wormhole geometries in fourth-order conformal Weyl gravity

Wormholes in generalized hybrid metric-Palatini gravity obeying the matter null energy condition everywhere

Dynamic thin-shell black-bounce traversable wormholes

Contact Info

Product

Resources

About