Related papers: Non-intercommuting Cosmic Strings
Axionic cosmic string solutions are investigated in a superstring motivated model with a pseudo-anomalous U(1) gauge symmetry. The inclusion of a gauge field and spatially varying dilaton allow local defect solutions with finite energy per…
We develop a semi-analytical model to describe the cosmological evolution of networks of cosmic strings with small-scale structure, by extending the velocity-dependent one-scale model to include an additional lengthscale describing the…
We review recent simulations of the formation of a particular class of non-topological defects known as semilocal strings during a phase transition. Semilocal strings have properties that are intermediate between topological cosmic strings…
We propose an alternative scenario to cosmic inflation for producing the initial seeds of cosmic structures. The cosmological fluctuations are generated by thermal fluctuation of the energy density of the ideal string gas in three compact…
A novel mechanism to produce a cosmic network of fundamental superstrings based on a time-varying string tension has been recently proposed. It has been found that fundamental superstrings can grow in a kinating background driven by the…
We derive the equations governing the dynamics of cosmic strings in a flat anisotropic universe of Bianchi type I and study the evolution of simple cosmic string loop solutions. We show that the anisotropy of the background can have a…
We investigate the effects of cosmological expansion on the spectrum of small-scale structure on a cosmic string. We simulate the evolution of a string with two modes that differ in wavelength by one order of magnitude. Once the short mode…
We perform numerical simulations of cosmic string evolution with intercommuting probability $P$ in the range $5\times 10^{-3}\le P\le 1$, both in the matter and radiation eras, using a modified version of the Allen-Shellard code. We find…
We study the behaviour of cosmic string networks in contracting universes, and discuss some of their possible consequences. We note that there is a fundamental time asymmetry between defect network evolution for an expanding universe and a…
Local cosmic strings solutions are introduced in a model with a pseudo-anomalous U(1) gauge symmetry. Such a symmetry is present in many superstring compactification models. The coupling of those strings with the axion necessary in order to…
We investigate nonthermal phase transitions that may occur after post-inflationary preheating in a simple model of a two-component scalar field with the effective potential $\lambda (\phi_i^2 - {\rm v}^2)^2/4$, where $\phi_1$ is identified…
In real-time lattice simulations of cosmic strings in the Abelian Higgs model, the broken translational invariance introduces lattice artefacts; relativistic strings therefore decelerate and radiate. We introduce two different methods to…
We discuss the cosmological evolution of cosmic strings with time-dependent tension. We show that, in the case that the tension changes as a power of time, the cosmic string network obeys the scaling solution: the characteristic scale of…
We present the properties of a cosmic superstring network in the scenario of flux compactification. An infinite family of strings, the (p,q)-strings, are allowed to exist. The flux compactification leads to a string tension that is periodic…
We examine current-carrying configurations of cosmic strings in non-Abelian gauge theories. We study the solutions numerically and point out that the currents will be at best dynamically stable and not subject to any topological…
The space-time dimensions transverse to a static straight cosmic string with a sufficiently large tension (supermassive cosmic strings) are compact and typically have a singularity at a finite distance form the core. In this paper, we…
We perform large-scale field theoretical simulations in expanding universe to characterize a network of strings that can form composed bound states. The network consists of two copies of Abelian Higgs strings (which we label p and q,…
We study the production of cosmological axions in the standard scenario in which a global string network forms at the Peccei-Quinn phase transition. We make detailed calculations of the axions produced by string loops (a previously…
We study the observational constraints for the axion models in string theory which can successfully act as quintessence. The evolution of the universe in this model is sensitive to the initial value of the axion field. This initial value of…
Previously developed analytic models for the evolution of cosmic string and monopole networks are applied to networks of monopoles attached to two or more strings; the former case is usually known as cosmic necklaces. These networks are a…