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Related papers: Cosmic String in Scalar-Tensor Gravity

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We consider a local cosmic string described by the Abelian-Higgs model in the framework of scalar-tensor gravities. We find the metric of the cosmic string in the weak-field approximation. The propagation of particles and light is analysed…

General Relativity and Quantum Cosmology · Physics 2016-08-15 Maria Emília X. Guimarães

We study the implications of a scalar-tensorial gravity for the metric of an isolated self-gravitating superconducting cosmic string. These modifications are induced by an arbitrary coupling of a massless scalar field to the usual tensorial…

General Relativity and Quantum Cosmology · Physics 2016-11-03 C. N. Ferreira , M. E. X. Guimaraes , J. A. Helayel-Neto

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…

General Relativity and Quantum Cosmology · Physics 2009-10-31 C. N. Ferreira , M. E. X. Guimaraes , J. A. Helayel-Neto

The gravitational field of both local and global non static cosmic strings in the context of Lyra geometry are investigated. Local strings are characterized by having an energy momentum tensor whose only non null components are $T_{tt} =…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Farook Rahaman

We study the effect of the geometry and topology of a scalar-tensor cosmic string space-time on the electric and magnetic fields of line sources. It is shown that the dilatonic coupling of the gravity induces effects along the string…

High Energy Physics - Theory · Physics 2009-11-10 I. V. L. Costa , F. A. Oliveira , M. E. X. Guimaraes , F. Moraes

We study spatial variations of the fine-structure constant in the presence of static straight cosmic strings in the weak-field approximation in Einstein gravity. We work in the context of a generic Bekenstein-type model and consider a gauge…

General Relativity and Quantum Cosmology · Physics 2009-11-11 J. Menezes , P. P. Avelino , C. Santos

We consider the possible existence of gravitationally bound stringlike objects in the framework of the generalized hybrid metric-Palatini gravity theory, in which the gravitational action is represented by an arbitrary function of the Ricci…

General Relativity and Quantum Cosmology · Physics 2021-12-21 Hilberto M. R. da Silva , Tiberiu Harko , Francisco S. N. Lobo , João Luís Rosa

It is well-known that some physical effects may arise in the spacetime of a straigth cosmic string due to its global conic properties. Among these effects, the vacuum polarization effect has been extensively studied in the litterature. In…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. E. X. Guimaraes

We consider the slowly rotating relativistic stars with a uniform angular velocity in the scalar-tensor gravity, and examine the rotational effect around such compact objects. For this purpose, we derive a 2nd order differential equation…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Hajime Sotani

We derive the geodesic equation of motion in the presence of weak gravitational fields produced by relativistic sources such as cosmic strings, decomposed into scalar, vector and tensor parts. We find that the vector (gravito-magnetic)…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-29 Miki Obradovic , Martin Kunz , Mark Hindmarsh , Ilian T. Iliev

We investigate the spacetime of a spinning cosmic string in conformal invariant gravity, where the interior consists of a gauged scalar field. We find exact solutions of the exterior of a stationary spinning cosmic string, where we write…

General Relativity and Quantum Cosmology · Physics 2020-04-15 Reinoud Jan Slagter

We study the effect of internal space rotation on the gravitational properties of infinite straight and stationary cosmic string. From the approximate solution of Einsten equations for the spinning Q-lump string we obtain long range…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Eugen Simanek

Gravitational and massless particle radiation of straight cosmic strings with finite thickness is studied analytically. It is found that the non-linear interaction of the radiation fields emitted by a cosmic string with the ones of the…

General Relativity and Quantum Cosmology · Physics 2009-07-07 Anzhong Wang , Nilton O. Santos

The thin string limit of Cosmic Strings is investigated using a description in terms of Colombeau's theory of nonlinear generalised functions. It is shown that in this description the energy-momentum tensor has a well defined thin string…

General Relativity and Quantum Cosmology · Physics 2007-05-23 K R P Sjodin , J A Vickers

Cosmic strings, as remnants of the symmetry breaking phase in the Early Universe, may be susceptible to non-local physics. Here we show that the presence of a Poincar\'e-invariant non-locality -- parametrized by a factor $\exp(-\Box\ell^2)$…

General Relativity and Quantum Cosmology · Physics 2021-02-16 Jens Boos

We reconsider the general properties of gravitational lensing effects induced by cosmic string systems, taking into account their equation of state and motion equations. We explicitly show that the deflection patterns induced by a string is…

Astrophysics · Physics 2009-10-31 Jean-Philippe Uzan , Francis Bernardeau

We combine and further develop ideas and techniques of Allen \& Ottewill, Phys. Rev.D, {\bf 42}, 2669 (1990) and Kay \& Studer Commun. Math. Phys., {\bf 139}, 103 (1991) for calculating the long range effects of cosmic string cores on…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Bruce Allen , Bernard S. Kay , Adrian C. Ottewill

We consider static and cylindrically symmetric interior string type solutions in the scalar-tensor representation of the hybrid metric-Palatini modified theory of gravity. As a first step in our study, we obtain the gravitational field…

General Relativity and Quantum Cosmology · Physics 2020-06-25 Tiberiu Harko , Francisco S. N. Lobo , Hilberto M. R. da Silva

Scalar fields with inverse power-law effective potentials may provide a negative pressure component to the energy density of the universe today, as required by cosmological observations. In order to be cosmologically relevant today, the…

High Energy Physics - Phenomenology · Physics 2016-09-06 Nicola Bartolo , Massimo Pietroni

We consider Kasner-type static, cylindrically symmetric interior string solutions in the $f\left(R,L_m\right)$ theory of modified gravity. The physical properties of the string are described by an anisotropic energy-momentum tensor…

General Relativity and Quantum Cosmology · Physics 2015-10-07 Tiberiu Harko , Matthew J. Lake
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