Wormhole solutions with a polynomial equation-of-state and minimal violation of the null energy condition

Abstract

This paper discusses wormholes supported by general equation-of-state , resulting in a significant combination of the linear equation-of-state and some other models. Wormhole with a quadratic equation-of-state is studied as a particular example. It is shown that the violation of null energy condition is restricted to some regions in the vicinity of the throat. The combination of barotropic and polytropic equation-of-state has been studied. We consider fluid near the wormhole throat in an exotic regime which at some r = r 1 , the exotic regime is connected to a distribution of asymptotically dark energy regime with −1 < ω < −1/3. We have presented wormhole solutions with small amount of exotic matter. We have shown that using different forms of equationof-state has a considerable effect on the minimizing violation of the null energy condition. The effect of many parameters such as redshift as detected by a distant observer and energy density at the throat on the r 1 is investigated. The solutions are asymptotically flat and compatible with presently available observational data at the large cosmic scale.

Minimally deformed wormholes

“…This information allows us to close the θ -system determining the full θ μν tensor (and, consequently, the full energy-momentum tensor of the solution) and the decoupler function, f (r ), therefore closing the problem at least from a mathematical point of view. This approach motivates and also allows to support the idea that these type of solutions can be constituted by the dark sector, which dominates our Universe [11][12][13][14][15][16][17][18][19][41][42][43]. Even more, it provides a possible interpretation of the contribution introduced by MGD.…”

“…Moreover, wormhole solutions with other type of symmetries have been investigated in [37][38][39] and also the possibility to obtain a traversable Schwarzschild-like wormhole has been considered [40]. Furthermore, recently [41] was studied and analyzed the behavior of wormhole structures in the realm of dark matter profiles, dark matter Bose-Einstein condensates [42] and non-linear equation of state [43], respectively.…”

Dynamical wormholes in Lovelock gravity

“…The general constraints on these functions have been discussed by Morris and Thorne in [3]. It is clear that if b(r) and φ(r) tend to zero the metric (7) reduces to a flat FLRW metric, and as R(t) → constant the static Morris-Thorne wormhole is recovered. In the model herein, we seek a way to determine the shape function b(r) and the scale factor R(t) in order to construct dynamical wormhole configurations.…”

“…For instance, in [6], a particular class of spacetime geometries admitting a traversable wormhole has been constructed using arbitrarily small quantities of exotic matter. In [7], it is shown that considering a general equation of state for the fluid profiles can act in favor of minimal usage of exotic matter. However, generalizing the matter sector may not necessarily guarantee obtaining a setting for nonexotic wormhole geometries [8].…”

Wormhole in f(R) gravity revisited

“…In this realm, the exotic matter can be confined to the shell. Wormhole with variable EoS [7] and polynomial EoS [8] are presented in the literature. In this class of solutions, the violation of NEC is restricted in some regions in the vicinity of the throat.…”