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Related papers: Scaling solution for small cosmic string loops

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The equation of circular loops of cosmic string with time-dependent tension is studied in the Minkowski spacetime and Robertson-Walker universe. We find that, in the case where the tension depends on some power of the cosmic time, cosmic…

High Energy Physics - Theory · Physics 2008-12-25 Hongbo Cheng , Yunqi Liu

Cosmic string networks form during cosmological phase transitions as a consequence of the Kibble mechanism. The evolution of the simplest networks is accurately described by the canonical Velocity Dependent One-Scale (VOS) model. However,…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-18 A. R. R. Almeida , C. J. A. P. Martins

The dynamics of cosmic strings is considered in anisotropic backgrounds. In particular, the behaviour of infinitely long straight cosmic strings and of cosmic string loops is determined. Small perturbations of a straight cosmic string are…

High Energy Physics - Theory · Physics 2012-04-25 Kerstin E. Kunze , Mairi Sakellariadou

We consider the possibility of a bosonic (meta)stabilization of a cosmic gauge string loop due to the presence of a gas of low mass bosonic particles which become trapped within the string core. This boson gas exerts a pressure which tends…

High Energy Physics - Theory · Physics 2013-03-11 J. R. Morris

We extend the scalar-tensor reconstruction techniques for classical cosmology frameworks, in the context of loop quantum cosmology. After presenting in some detail how the equations are generalized in the loop quantum cosmology case, we…

General Relativity and Quantum Cosmology · Physics 2016-08-24 V. K. Oikonomou

Cosmological evolution of axionic string network is analyzed in terms of field-theoretic simulations in a box of 512^3 grids, which are the largest ever, using a new and more efficient identification scheme of global strings. The scaling…

High Energy Physics - Phenomenology · Physics 2011-06-30 Takashi Hiramatsu , Masahiro Kawasaki , Toyokazu Sekiguchi , Masahide Yamaguchi , Jun'ichi Yokoyama

Numerical simulations of Nambu-Goto cosmic strings in an expanding universe show that the loop distribution relaxes to an universal configuration, the so-called scaling regime, which is of power law shape on large scales. Precise…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-13 Pierre Auclair , Christophe Ringeval , Mairi Sakellariadou , Daniele Steer

We study the decay of cosmic string loops in the Abelian-Higgs model. We confirm earlier results that loops formed by intersections of infinite strings formed from random-field initial conditions disappear quickly, with lifetime…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-25 Mark Hindmarsh , Joanes Lizarraga , Ander Urio , Jon Urrestilla

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

Using a new parallel computing technique, we have run the largest cosmic string simulations ever performed. Our results confirm the existence of a long transient period where a non-scaling distribution of small loops is produced at lengths…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 Jose J. Blanco-Pillado , Ken D. Olum , Benjamin Shlaer

Numerical simulations and analytical models suggest that infinite cosmic strings produce cosmic string loops of all sizes with a given power-law. Precise estimations of the power-law exponent are still matter of debate while numerical…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-26 Pierre G. Auclair

The order of magnitude of energy emission from cusps to light bosons on ordinary cosmic strings is calculated perturbatively. The analysis is applicable to both closed string loops and long cosmic strings. The perturbative result obtained…

High Energy Physics - Phenomenology · Physics 2009-10-22 Masoud Mohazzab

Exact solutions of the Einstein field equations with cosmic string and space varying cosmological constant, viz., $\Lambda= \Lambda(r)$, in the energy-momentum tensors are presented. Three cases have been studied: where variable…

Astrophysics · Physics 2009-07-22 Saibal Ray , Farook Rahaman , Utpal Mukhopadhyay

The gravitational back-reaction on a certain type of rigidly-rotating cosmic string loop, first discovered by Allen, Casper and Ottewill, is studied at the level of the weak-field approximation. The near-field metric perturbations are…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Malcolm Anderson

This is a short review on strings in curved spacetimes. We start by recalling the classical and quantum string behaviour in singular plane waves backgrounds. We then report on the string behaviour in cosmological spacetimes (FRW, de Sitter,…

High Energy Physics - Theory · Physics 2007-05-23 H. J. de Vega

Progress in string theory has resulted in a whole landscape of vacua solutions.In this talk I describe a proposal for exploring the cosmological implications of the landscape, based on the dynamics of the wavefunction of the universe…

High Energy Physics - Phenomenology · Physics 2009-11-11 Laura Mersini-Houghton

The collisions of cosmic strings loops and the dynamics of junctions formations in expanding backgrounds are studied. The key parameter controlling the dynamics of junctions formation, the cosmic strings zipping and unzipping is the…

High Energy Physics - Theory · Physics 2015-03-13 Hassan Firouzjahi , Salomeh Khoeini-Moghaddam , Shahram Khosravi

I propose a reinterpretation of cosmic dark matter in which a rigid network of cosmic strings formed at the end of inflation. The cosmic strings fulfill three functions: At recombination they provide an accretion mechanism for virializing…

High Energy Physics - Theory · Physics 2009-07-22 Stephon Alexander

The field equations for a time dependent cylindrical cosmic string coupled to gravity are reformulated in terms of geometrical variables defined on a 2+1-dimensional spacetime by using the method of Geroch decomposition. Unlike the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 K R P Sjodin , U Sperhake , J A Vickers

We study cosmic strings in the complex symmetron model, a scalar-tensor theory with a spontaneously broken local $U(1)$ symmetry in low matter density regions. Using numerical simulations, we show that these strings preferentially attach to…

High Energy Physics - Phenomenology · Physics 2025-08-19 Ali Nezhadsafavi , Levon Pogosian