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We discuss and summarise the predictions of a model for the non-equilibrium evolution of a network of cosmic strings initially containing {\em only loops} and {\em no infinite strings}. The results are of interest given recent work…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. A. Steer

We present results from a detailed numerical study of the small-scale and loop production properties of cosmic string networks, based on the largest and highest resolution string simulations to date. We investigate the non-trivial fractal…

Astrophysics · Physics 2008-11-26 C. J. A. P. Martins , E. P. S. Shellard

The cosmic string scenario in an open universe is developed -- including the equations of motion, a model of network evolution, the large angular scale CMB temperature anisotropy, and the power spectrum of density fluctuations produced by…

Astrophysics · Physics 2009-10-30 P. P. Avelino , R. R. Caldwell , C. J. A. P. Martins

We investigate scaling and correlations of the energy and momentum in an evolving network of cosmic strings in Minkowski space. These quantities are of great interest, as they must be understood before accurate predictions for the power…

Astrophysics · Physics 2009-10-28 Graham R. Vincent , Mark Hindmarsh , Mairi Sakellariadou

We use the Velocity-dependent One Scale Model for topological defect evolution to explore and classify the possible scaling solutions for string networks with time-varying tension, in cosmological and non-cosmological settings and under two…

High Energy Physics - Phenomenology · Physics 2026-02-24 C. S. C. M. Coelho , A. -L. Y. Gschrey , C. J. A. P. Martins

Global topological defects produce nonzero stress-energy throughout spacetime, and as a result can have observable gravitational influence on surrounding matter. Gravitational effects of global strings are used to place bounds on their…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Shane L. Larson , William A. Hiscock

We review the properties and evolution of strings networks containing both a spectrum of string tensions as well as Y-junctions, namely a point at which three different strings meet. Such a situation is expected in cosmic superstring…

High Energy Physics - Theory · Physics 2015-06-17 D. A. Steer

We study the evolution of cosmic strings taking into account the frictional force due to the surrounding radiation. We consider small perturbations on straight strings, oscillation of circular loops and small perturbations on circular…

High Energy Physics - Theory · Physics 2009-10-22 J. Garriga , M. Sakellariadou

The properties of string networks at scales well below the horizon are poorly understood, but they enter critically into many observables. We argue that in some regimes, stretching will be the only relevant process governing the evolution.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Joseph Polchinski , Jorge V. Rocha

We report on a large scale numerical study of networks of semilocal cosmic strings in flat space in the parameter regime in which they are perturbatively stable. We find a population of segments with an exponential length distribution and…

Astrophysics · Physics 2008-11-26 A. Achucarro , P. Salmi , J. Urrestilla

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…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ana Achúcarro , Julian Borrill , Andrew R. Liddle

We study the formation and evolution of an interconnected string network in large-scale field-theory numerical simulations, both in flat spacetime and in expanding universe. The network consists of gauge U(1) strings of two different kinds…

High Energy Physics - Theory · Physics 2008-11-26 Jon Urrestilla , Alexander Vilenkin

Topological defects are ubiquitous in condensed-matter physics but only hypothetical in the early universe. In spite of this, even an indirect evidence for one of these cosmic objects would revolutionize our vision of the cosmos. We give…

Astrophysics · Physics 2007-05-23 Alejandro Gangui

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…

Astrophysics · Physics 2009-10-22 R. A. Battye , E. P. S. Shellard

We present an analytic model specifically designed to address the long standing issue of small scale structure on cosmic string networks. The model is derived from the microscopic string equations, together with a few motivated assumptions.…

General Relativity and Quantum Cosmology · Physics 2008-12-23 Jorge V. Rocha

We set up and analyse a model for the non-equilibrium evolution of a network of cosmic strings initially containing only loops and no infinite strings. Due to this particular initial condition, our analytical approach differs significantly…

High Energy Physics - Phenomenology · Physics 2009-10-31 E. J. Copeland , T. W. B. Kibble , D. A. Steer

We describe a numerical simulation of the evolution of an $S_3$ cosmic string network which takes fully into account the non-commutative nature of the cosmic string fluxes and the topological obstructions which hinder strings from moving…

Astrophysics · Physics 2009-10-30 Patrick N. McGraw

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…

Astrophysics · Physics 2008-11-26 Louis Leblond , Mark Wyman

The string-dominated universe locally resembles an open universe, and fits dynamical measures of power spectra, cluster abundances, redshift distortions, lensing constraints, luminosity and angular diameter distance relations and microwave…

Astrophysics · Physics 2009-10-28 David Spergel , Ue-Li Pen

We study the production of loops in the cosmic string network in the expanding background by means of a numerical simulation exact in the flat-spacetime limit and first-order in the expansion rate. We find an initial regime characterized by…

Astrophysics · Physics 2008-11-26 Ken D. Olum , Vitaly Vanchurin