Phantom fluid supporting traversable wormholes in alternative gravity with extra material terms

Abstract

Wormholes are tunnels connecting different regions in space-time. They were obtained originally as a solution for Einstein's General Relativity theory and according to this theory they need to be filled by an exotic kind of anisotropic matter. In the present sense, by "exotic matter" we mean matter that does not satisfy the energy conditions. In this article we propose the modelling of wormholes within an alternative gravity theory that proposes an extra material (rather than geometrical) term in its gravitational action. Our solutions are obtained from well-known particular cases of the wormhole metric potentials, named redshift and shape functions, and yield the wormholes to be filled by a phantom fluid, that is, a fluid with equation of state parameter ω < −1. In possession of the solutions for the wormhole material content, we also apply the energy conditions to them. The features of those are carefully discussed.

Dynamical wormholes in Einstein–Gauss–Bonnet gravity

“…However, one can easily show that for t = 0 the WEC is satisfied by imposing the negative value α, due to the presence of the last term in Eqs. (35)- (36). We can also suitably choose the constants so that the WEC be satisfied in whole spacetime, Fig.…”

“…Also, a large amount a e-mail: mehdizadeh.mr@uk.ac.ir (corresponding author) of work has been devoted to build and study wormhole solutions within the framework of modified gravity theories among which we quote: wormhole solutions in Brans-Dicke theory [17][18][19][20], f (R) gravity [21][22][23], Born-Infeld theory [24,25], third order Lovelock theory [26], Kaluza-Klein gravity [27,28], scalar-tensor gravity [29] and solutions in the presence of a cosmological constant have been reported in [30,31]. Recently, the possibility of existence of traversable wormholes in the context of f (R, T ) gravity have been reported in the literature, such as wormhole formation with two types of varying Chaplygin gas [32], wormhole solutions satisfying the energy conditions in the exponential f (R, T ) gravity [33], see also [34][35][36][37][38] for other solutions in this theory.…”

Late-time viscous cosmology in f(R, T) gravity

“…In this work we shall work with f (R, T) gravity theory in which the Ricci scalar R is replaced with a suitable functional form of R and trace of energy momentum tensor T [43] and therefore is a straightforward conjecture to f (R) gravity (see [44,45]). f (R, T) gravity have proved to be successful in numerous cosmological sectors such as dark matter [46] dark energy [47], massive pulsars [48,49], super-Chandrasekhar white dwarfs [50], wormholes [51][52][53][54][55][56][57][58][59][60][61], gravitational waves [62][63][64], bouncing cosmology [65,66], baryogenesis [67,68], Big-Bang nucleosynthesis [69] and in varying speed of light scenarios [70]. The article is methodized as follows: In Section II we provide a summary of f (R, T) gravity and solve the field equations assuming a bulk viscous fluid.…”

Collapsing Wormholes Sustained by Dustlike Matter

“…Wormholes have been considered in various theories of gravity, including the Brans-Dicke theory of gravity [8], in the Einstein-Born-Infeld theory of gravity [9], in the Einstein-Gauss-Bonnet theory [10], in f (R) gravity [11], in Rastall's theory of gravity [12] and many other theories. Various models of matter were considered as a source of wormholes: scalar and electromagnetic fields [9,13,14], Chaplygin gas [15], various models of phantom energy and quintessence, including models of matter with the structure of the energy-momentum tensor of a perfect fluid [16][17][18][19][20]. Models of wormholes were also built using the thin-shell formalism, the works of [21,22] being among the first.…”