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Related papers: Effects of friction on cosmic strings

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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 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

In this paper, we study the equation of circular loops with time-dependant tension in the BTZ black hole background. We obtain various cases where cosmic string loops finally collapse to form black holes. Also, we study effect of the BTZ…

High Energy Physics - Theory · Physics 2011-08-24 J. Sadeghi , H. M. Farahani , B. Pourhassan , S. M. Noorbakhsh

In theories with cosmic strings, a small fraction of string loops may collapse to form black holes. In this Letter, various constraints on such models involving black holes are considered. Hawking radiation from black holes, gamma and…

Astrophysics · Physics 2009-10-30 Jane H. MacGibbon , Robert H. Brandenberger , U. F. Wichoski

Cosmic strings that are attached to rapidly spinning black holes can extract significant amounts of rotational energy and angular momentum. Here we study the effect on primordial black holes, which are expected to form with one or more…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-10 Sameer Ahmed , Michael J. Kavic , Steven L. Liebling , Matthew Lippert , Mohammad Mian , John Simonetti

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

The cosmological features of primordial black holes formed from collapsed cosmic string loops are studied. Observational restrictions on a population of primordial black holes are used to restrict $f$, the fraction of cosmic string loops…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. R. Caldwell , E. Gates

We consider the evolution of a cosmic string loop that is captured by a much more massive and compact black hole. We show that after several reconnections that produce ejections of smaller loops, the loop that remains bound to the black…

High Energy Astrophysical Phenomena · Physics 2021-04-28 Hengrui Xing , Yuri Levin , Andrei Gruzinov , Alexander Vilenkin

We study the deformation of a long cosmic string by a nearby rotating black hole. We examine whether the deformation of a cosmic string, induced by the gravitational field of a Kerr black hole, may lead to the formation of a loop of cosmic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Florian Dubath , Mairi Sakellariadou , Claude Michel Viallet

Cosmic strings and primordial black holes (PBHs) commonly and naturally form in many scenarios describing the early universe. Here we show that if both cosmic strings and PBHs are present, their interaction leads to a range of interesting…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-14 Alexander Vilenkin , Yuri Levin , Andrei Gruzinov

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

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

We include the effect of the frictional force caused by interactions between cosmic strings and the particles of the background plasma in the computation of the stochastic gravitational wave background generated by cosmic string loops.…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-23 S. Mukovnikov , L. Sousa

We present the first fully general relativistic dynamical simulations of Abelian Higgs cosmic strings using 3+1D numerical relativity. Focusing on cosmic string loops, we show that they collapse due to their tension and can either (i)…

General Relativity and Quantum Cosmology · Physics 2019-05-22 Thomas Helfer , Josu C. Aurrekoetxea , Eugene A. Lim

A small fraction, $f$, of cosmic string loops can collapse to form Primordial Black Holes (PBHs). Constraints on the abundance of PBHs can therefore be used to constrain $f$. We update these calculations, taking into account the PBH…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Chloe James-Turner , Danton P. B. Weil , Anne M. Green , Edmund J. Copeland

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

We study the effect of free streaming in a universe with cosmic strings with time-varying tension as well as with constant tension. Although current cosmological observations suggest that fluctuation seeded by cosmic strings cannot be the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Tomo Takahashi , Masahide Yamaguchi

This paper discusses the gravitational scattering of a straight, infinitely long test cosmic string by a black hole. We present numerical results that probe the two-dimensional parameter space of impact parameter and initial velocity and…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Jean-Pierre De Villiers , Valeri Frolov

In this work the equation of circular loops of cosmic string possessing time-dependent tension is studied in the de Sitter spacetime. We find that the cosmic string loops with initial radius $r(t_{0})>0.707L$, L de Sitter radius, should not…

High Energy Physics - Theory · Physics 2009-03-24 Yunqi Liu , Hongbo Cheng

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…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Christian Stephan-Otto , Ken D. Olum , Xavier Siemens
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