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Related papers: Fractional Cosmic String Loops In Expanding Univer…

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The existence of a scaling evolution for cosmic string loops in an expanding universe is demonstrated for the first time by means of numerical simulations. In contrast with what is usually assumed, this result does not rely on any…

Astrophysics · Physics 2009-11-13 Christophe Ringeval , Mairi Sakellariadou , Francois Bouchet

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

It has recently been realised that strings with time-dependent tensions exhibit interesting dynamics; in particular, when the tension decreases loops of string can grow and possibly percolate. We extend previous analytic studies of strings…

High Energy Physics - Theory · Physics 2026-01-09 Hubert Lau Sze Chun , Joseph Conlon

We study the cosmological implications of the one-loop terms in the string expansion. In particular, we find non-singular solutions which interpolate between a contracting universe and an expanding universe, and show that these solutions…

High Energy Physics - Theory · Physics 2009-10-30 Richard Easther , Kei-ichi Maeda

In this paper the equation of circular loops of cosmic string with periodic tension is investigated in the Minkowski spacetime and Robertson-Walker universe respectively. We find that the cosmic string loops possessing this kind of…

High Energy Physics - Theory · Physics 2015-06-05 Leilin Wang , Hongbo Cheng

We investigate the evolution of the homogeneous and isotropic universe within the framework of the effective string gravity with string-loop modifications of dilaton couplings. In the case of barotropic perfect fluid as a nongravitational…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. A. Saharian

We study the effects of friction on the scaling evolution of string networks in condensed matter and cosmological contexts. We derive a generalized `one-scale' model with the string correlation length $L$ and velocity $v$ as dynamical…

High Energy Physics - Phenomenology · Physics 2016-09-01 C. J. A. P. Martins , E. P. S. Shellard

We describe the detailed study and results of high-resolution numerical simulations of string-induced structure formation in open universes and those with a non-zero cosmological constant. The effect from small loops generated from the…

Astrophysics · Physics 2009-09-25 J. H. P. Wu , P. P. Avelino , E. P. S. Shellard , B. Allen

At early stages the dynamics of cosmic string networks is expected to be influenced by an excessive production of small loops at the scales of initial conditions l_{min}. To understand the late time behavior we propose a very simple…

High Energy Physics - Theory · Physics 2014-11-21 Vitaly Vanchurin

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

We study the impact of fragmentation on the cosmic string loop number density, using an approach inspired by the three-scale model and a Boltzmann equation. We build a new formulation designed to be more amenable to numerical resolution and…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-12 Pierre Auclair

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 investigate the evolution of matter density perturbations within a fractional cosmological framework inspired by fractal space-time constructions in field theory, where a deformation of the integration measure induces non-locality and…

General Relativity and Quantum Cosmology · Physics 2026-04-24 S. M. M. Rasouli

We apply the dynamical systems tools to study the (linear) dynamics of Friedmann-Robertson-Walker universes that are fuelled by non-linear electrodynamics. We focus, mainly, in two particular models. In the first model the cosmic evolution…

General Relativity and Quantum Cosmology · Physics 2009-05-08 Ricardo Garcia-Salcedo , Tame Gonzalez , Claudia Moreno , Israel Quiros

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 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

The evolution of cosmic string networks is an interesting dynamical problem. The equations governing these networks are classical and fully specified, but the length scale at which cosmic string loops form has been uncertain to tens of…

Astrophysics · Physics 2009-06-23 Joseph Polchinski

We develop an exact functional method applied to the bosonic string on a shperical world sheet, in graviton and dilaton backgrounds, consistent with conformal invariance. In this method, quantum fluctuations are controled by the amplitude…

High Energy Physics - Theory · Physics 2007-05-23 Jean Alexandre , Nick E. Mavromatos

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

The discrete quantum geometric effects play an important role in dynamical evolution in the loop quantum cosmology. These effects which are significant at the high energies lead to the quadratic energy density modifications to the Friedmann…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Parampreet Singh
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