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Related papers: Accretion onto Oscillating Cosmic String Loops

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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 dynamics of circular cosmic string loops in a spatially flat Friedmann Lema\^itre Robertson Walker universe within a fractional Polyakov framework that incorporates nonlocal memory effects. Allowing both the loop radius and…

High Energy Physics - Theory · Physics 2026-04-30 Pankaj Chaturvedi , Bikram Nath

We investigate the contribution made by small loops from a cosmic string network as seeds for large-scale structure formation. We show that cosmic string loops are highly correlated with the long-string network on large scales and therefore…

Astrophysics · Physics 2008-11-26 P. P. Avelino , E. P. S. Shellard , J. H. P. Wu , B. Allen

We simulate the formation of cosmic strings at the zeros of a complex Gaussian field with a power spectrum $P(k) \propto k^n$, specifically addressing the issue of the fraction of length in infinite strings. We make two improvements over…

High Energy Physics - Phenomenology · Physics 2009-10-30 Robert J. Scherrer , Alexander Vilenkin

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

With the hypothesis that cosmic string loops act as seeds for globular clusters in mind, we study the role that velocities of these strings will play in determining the mass distribution of globular clusters. Loops with high enough…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-09 Ling Lin , Shoma Yamanouchi , Robert Brandenberger

We hypothesize that cosmic string loops are the seeds about which globular clusters accrete. Fixing the cosmic string tension by demanding that the peak in the distribution of masses of objects accreting onto string loops agrees with the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Alistair Barton , Robert H. Brandenberger , Ling Lin

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

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 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 apply the adhesion approximation to study the formation and evolution of voids in the Universe. Our simulations -- carried out using 128$^3$ particles in a cubical box with side 128 Mpc -- indicate that the void spectrum evolves with…

Astrophysics · Physics 2009-10-22 Varun Sahni , B. S. Sathyaprakash , Sergei F. Shandarin

The mean spectrum and burst statistics of gravitational waves produced by a cosmological population of cosmic string loops are estimated using analytic approximations, calibrated with earlier simulations. Formulas are derived showing the…

Astrophysics · Physics 2009-11-11 Craig J. Hogan

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 examine the scaling properties of an evolving network of strings in Minkowski spacetime and study the evolution of length scales in terms of a 3-scale model proposed by Austin, Copeland and Kibble (ACK). We find good qualitative and some…

Astrophysics · Physics 2008-11-26 Graham R. Vincent , Mark Hindmarsh , Mairi Sakellariadou

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

Cosmic superstrings are produced towards the end of the brane inflation. If the string tension is low enough, loops tend to be relatively long-lived. The resultant string network is expected to contain many loops which are smaller than…

Astrophysics · Physics 2007-09-10 David F. Chernoff , S. -H. Henry Tye

We examine variations in the equation of state of the cosmic string portion of the cosmological fluid which lead to perturbations of the background matter density. These fluctuations in the equation of state are due to variations in the…

Astrophysics · Physics 2010-01-06 Pedro Avelino , Robert Caldwell

We consider one-loop corrections to the bispectrum and skewness of cosmological density fluctuations induced by gravitational evolution. As has been established by comparison with numerical simulations, tree-level perturbation theory (PT)…

Astrophysics · Physics 2009-10-28 Roman Scoccimarro

The equation of cosmic string loops in Kerr-de Sitter spacetimes is derived. Having solved the equation numerically, we find that the loops can expand and exist except for too small ones.

High Energy Physics - Theory · Physics 2009-03-19 Zhengyan Gu , Hongbo Cheng

The problem of the late accretion phase of the evolution of an axisymmetric, isothermal magnetic disk surrounding a forming star has been formulated in a companion paper. The "central sink approximation" is used to circumvent the problem of…

Astrophysics · Physics 2009-11-10 Konstantinos Tassis , Telemachos Ch. Mouschovias