Related papers: Cosmic strings and strings in gravitational waves
We study the perturbative dynamics of an infinite gravitating Nambu-Goto string within the general-relativistic perturbation framework. We develop the gauge invariant metric perturbation on a spacetime containing a self-gravitating straight…
We derive a general procedure for calculating the gravitational wave background (GWB) from cosmic string loops whose typical shape evolves over time, as in gravitational backreaction. Using the results of a large-scale study of numerical…
The motion of a string in curved spacetime is discussed in detail. The basic formalism for string motion in Minkowski spacetime and in curved spacetime is presented. The description applies to cosmic strings as well as to fundamental…
We study the self-similar motion of a string in a self-similar spacetime by introducing the concept of a self-similar string, which is defined as the world sheet to which a homothetic vector field is tangent. It is shown that in Nambu-Goto…
We examine the leading order corrections to the Nambu effective action for the motion of a cosmic string, which appear at fourth order in the ratio of the width to radius of curvature of the string. We determine the numerical coefficients…
Cosmic strings represent an attractive source of gravitational waves (GWs) from the early Universe. However, numerical computation of the GW signal from cosmic strings requires the evaluation of complicated integral and sum expressions,…
We construct cosmological spacetimes with null Kasner-like singularities as purely gravitational solutions with no other background fields turned on. These can be recast as anisotropic plane-wave spacetimes by coordinate transformations. We…
In this paper, we study the various cylindrical solutions (cosmic strings) in gravity's rainbow scenario. In particular, we calculate the gravitational field equations corresponding to energy-dependent background. Further, we discuss the…
We consider the metric perturbations around a stationary rotating Nambu-Goto string in Minkowski spacetime. By solving the linearized Einstein equations, we study the effects of azimuthal frame-dragging around the rotation axis and linear…
The perturbative modes propagating along an infinite string are investigated within the framework of the gauge invariant perturbation formalism on a spacetime containing a self-gravitating straight string with a finite thickness. These…
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…
In this paper we study the motion of a rigidly rotating Nambu-Goto test string in a stationary axisymmetric background spacetime. As special examples we consider the rigid rotation of strings in flat spacetime, where explicit analytic…
Comparison of the oscillatory behavior of a gravitating infinite Nambu-Goto string and a test string is investigated using the general relativistic gauge invariant perturbation technique with two infinitesimal parameters on a flat spacetime…
If the Universe underwent a cosmic phase transition, it may have left behind a network of cosmic strings. When these strings arise from the breaking of a gauge symmetry, their decay produces a significant stochastic background of…
Time evolution of a circular cosmic string loop is investigated by numerically solving the field equations for the scalar and the gauge fields consisting of the vortex. It is shown that the result agrees with an analytic estimate based on…
An implicit, fully characteristic, numerical scheme for solving the field equations of a cosmic string coupled to gravity is described. The inclusion of null infinity as part of the numerical grid allows us to apply suitable boundary…
We develop a method for computing the linearized gravitational backreaction for Nambu-Goto strings using a fully covariant formalism. We work with equations of motion expressed in terms of a higher dimensional analog of the geodesic…
Null cosmic strings are shown to disturb gravitational fields of massive bodies and create outgoing gravitational waves (GW). Perturbations of the metric caused by a straight null string and a point-like massive source are found as…
Static and stationary cylindrically symmetric space-times in general relativity are considered, supported by distributions of cosmic strings stretched in the azimuthal ($\varphi$), longitudinal ($z$) or radial ($x$) directions or and by…
We compute the stochastic gravitational wave background generated by cosmic superstrings using a semi-analytical velocity-dependent model to describe their dynamics. We show that heavier string types may leave distinctive signatures on the…