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Related papers: Fractional Cosmic String Loops In Expanding Univer…

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The dynamical evolution of superconducting cosmic string loops with specific equations of state describing timelike and spacelike currents is studied numerically. This analysis extends previous work in two directions: first it shows results…

High Energy Physics - Phenomenology · Physics 2009-11-07 Adriana Cordero-Cid , Xavier Martin , Patrick Peter

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 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…

Astrophysics · Physics 2009-11-07 P. P. Avelino , C. J. A. P. Martins

The dynamical evolution of superconducting cosmic strings is much more complicated than that of simple Goto-Nambu strings. For this reason, there are only a few known analytical solutions and no numerical ones. The goal of this paper is to…

High Energy Physics - Phenomenology · Physics 2007-05-23 X. Martin , P. Peter

We analyze the shapes of cosmic string loops found in large-scale simulations of an expanding-universe string network. The simulation does not include gravitational back reaction, but we model that process by smoothing the loop using…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-30 Jose J. Blanco-Pillado , Ken D. Olum , Benjamin Shlaer

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

We develop a model of string dynamics with back-reaction from both scaling and non-scaling loops taken into account. The evolution of a string network is described by the distribution functions of coherence segments and kinks. We derive two…

High Energy Physics - Theory · Physics 2010-11-19 Vitaly Vanchurin

Cosmic string loops are non-linear density fluctuations which form in the early universe and could play an important role in explaining many phenomena which are in tension with the standard $\Lambda$CDM model. Hence, the details of the…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-11 Hao Jiao , Bryce Cyr , Robert Brandenberger

A novel mechanism for the production of a cosmic network of fundamental superstrings based on a time-varying string tension has been recently proposed in the context of a kinating background driven by the volume modulus of string…

High Energy Physics - Theory · Physics 2025-03-17 Luca Brunelli , Michele Cicoli , Francisco G. Pedro

Aspects of string cosmology for critical and non-critical strings are discussed emphasizing the necessity to account for the dilaton dynamics for a proper incorporation of ``large - small" duality. This drastically modifies the intuition…

High Energy Physics - Theory · Physics 2009-09-17 A. A. Tseytlin , C. Vafa

We extend and develop our previous work on the evolution of a network of cosmic strings. The new treatment is based on an analysis of the probability distribution of the end-to-end distance of a randomly chosen segment of left-moving string…

High Energy Physics - Phenomenology · Physics 2016-09-01 Daren Austin , E. J. Copeland , T. W. B. Kibble

We propose a mechanism for the creation of cosmic string loops with dynamically stabilised windings in the internal space. Assuming a velocity correlations regime in the post-inflationary epoch, such windings are seen to arise naturally in…

High Energy Physics - Theory · Physics 2014-01-28 Matthew Lake , Steven Thomas , John Ward

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…

Astrophysics · Physics 2009-10-22 Michiyasu Nagasawa , Jun'ichi Yokoyama

We consider the kinematical and dynamical evolution of Friedmann universes with a mixture of non-interacting matter and a ghost-like field, in a scenario analogous to that advocated by the Quintom model. Assuming that the conventional…

General Relativity and Quantum Cosmology · Physics 2020-10-28 Ameya Chavda , John D. Barrow , Christos G. Tsagas

In the context of a cosmological string model describing the propagation of strings in a time-dependent Robertson-Walker background space-time, we show that the asymptotic acceleration of the Universe can be identified with the square of…

High Energy Physics - Theory · Physics 2009-09-11 John Ellis , N. E. Mavromatos , D. V. Nanopoulos

We study the classical dynamics of a bosonic string in the $D$--dimensional flat Friedmann--Robertson--Walker and Schwarzschild backgrounds. We make a perturbative development in the string coordinates around a {\it null} string…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Carlos O. Lousto , N. Sanchez

We consider the evolution of correlation functions in a non-Markov version of the contact model in the continuum. The memory effects are introduced by assuming the fractional evolution equation for the statistical dynamics. This leads to a…

Mathematical Physics · Physics 2014-12-02 Anatoly N. Kochubei , Yuri G. Kondratiev

Dynamical systems methods are used to investigate global behavior of the spatially flat Friedmann-Robertson-Walker cosmological model in gravitational theory with a non-minimally coupled scalar field and a constant potential function. We…

General Relativity and Quantum Cosmology · Physics 2015-11-11 Orest Hrycyna , Marek Szydlowski

We investigate some classical aspects of fundamental strings via numerical experiments. In particular, we study the thermodynamics of a string network within a toroidal universe, as a function of string energy density and space…

High Energy Physics - Theory · Physics 2009-10-28 Mairi Sakellariadou

A general class of cosmological models driven by a nonlocal scalar field inspired by the string field theory is studied. Using the fact that the considering linear nonlocal model is equivalent to an infinite number of local models we have…

High Energy Physics - Theory · Physics 2008-11-26 I. Ya. Aref'eva , L. V. Joukovskaya , S. Yu. Vernov