Cosmic String in Scalar-Tensor Gravity
نویسنده
چکیده
The gravitational properties of a local cosmic string in the framework of scalar-tensor gravity are examined. We find the metric in the weak-field approximation and we show that, contrary to the General Relativity case, the cosmic string in scalar-tensor gravitation exerces a force on non-relativistic, neutral test particle. This force is proportional to the derivative of the conformal factor A(φ) and it is always attractive. Moreover, this force could have played an important role at the Early Universe, although nowadays it can be neglegible. It ∗e-mail: [email protected]
منابع مشابه
تبدیلات دوگانگی آبلی استاندارد در گرانش f(T)
According to the perturbation order, the equations of motion of low-energy string effective action are the generalized Einstein equations. Thus, by making use of the conformal transformation of the metric tensor, it is possible to map the low-energy string effective action into f(T) gravity, relating the dilaton field to the torsion scalar. Considering a homogeneous and isotropic universe and ...
متن کاملCurrent-Carrying Cosmic Strings in Scalar-Tensor Gravities
We study the modifications on the metric of an isolated self-gravitating bosonic superconducting cosmic string in a scalar-tensor gravity in the weak-field approximation. These modifications are induced by an arbitrary coupling of a massless scalar field to the usual tensorial field [email protected] [email protected] Also at Grupo de F́ısica Teórica, Universidade Católica de Petrópolis. hela...
متن کاملBulk viscous string cosmological models in Saez – Ballester theory of gravitation
Spatially homogeneous Bianchi type-II, VIII and IX anisotropic, as well as isotropic cosmological models can be obtained in a scalar tensor theory of gravitation proposed by Saez and Ballester (1986) when the source for energy momentum tensor is a bulk viscous fluid containing one-dimensional cosmic strings. All the models obtained and presented here are expanding, non-rotating and accelerating...
متن کاملSupermassive screwed cosmic string in dilaton gravity
The early Universe might have undergone phase transitions at energy scales much higher than the one corresponding to the Grand Unified Theories (GUT) scales. Then, at these higher energy scales, the transition at which gravity separated from all other interactions, the Planck era, more massive strings called supermassive cosmic strings, could be produced, with energy of about 10GeV . The dynami...
متن کاملStrange quark matter attached to string cloud in general scalar tensor theory of gravitation
Bianchi type-VI0 space time with strange quark matter attached to string cloud in Nordtvedt [1] general scalar tensor theory of gravitation with the help of a special case proposed by Schwinger [2] is obtained. The field equations have been solved by using the anisotropy feature of the universe in the Bianchi type-VI0 space time. Some important features of the model, thus obtained, have been di...
متن کامل