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Related papers: Cosmic string loops in the expanding universe

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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

We present results of new field-theoretic simulation of cosmological axion strings, which are eight times longer than previous ones. We have upgraded our simulation of physical strings in Hiramatsu et al. (2011) in terms of the number of…

High Energy Physics - Phenomenology · Physics 2019-12-06 Masahiro Kawasaki , Toyokazu Sekiguchi , Masahide Yamaguchi , Jun'ichi Yokoyama

We investigate the contribution of cosmic string loops to the Cosmic Microwave Background (CMB) anisotropies. This is done by extending the Unconnected Segment Model (USM) to include the contribution of the cosmic string loops created…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-14 I. Yu. Rybak , L. Sousa

Cosmic string loops are defined by a pair of periodic functions ${\bf a}$ and ${\bf b}$, which trace out unit-length closed curves in three-dimensional space. We consider a particular class of loops, for which ${\bf a}$ lies along a line…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Bruce Allen , Paul Casper , Adrian Ottewill

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 fraction of cosmic string loops which collapse to form black holes is estimated using a set of realistic loops generated by loop fragmentation. The smallest radius sphere into which each cosmic string loop may fit is obtained by…

General Relativity and Quantum Cosmology · Physics 2009-10-28 R. R. Caldwell , Paul Casper

We examine the rates at which energy and momentum are radiated into gravitational waves by a large set of realistic cosmic string loops. The string loops are generated by numerically evolving parent loops with different initial conditions…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Paul Casper , Bruce Allen

We present the properties of a cosmic superstring network in the scenario of flux compactification. An infinite family of strings, the (p,q)-strings, are allowed to exist. The flux compactification leads to a string tension that is periodic…

Astrophysics · Physics 2008-11-26 Louis Leblond , Mark Wyman

We study the approach to scaling in axion string networks in the radiation era, through measuring the root-mean-square velocity $v$ as well as the scaled mean string separation $x$. We find good evidence for a fixed point in the phase-space…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-02 Mark Hindmarsh , Joanes Lizarraga , Asier Lopez-Eiguren , Jon Urrestilla

Motivated by recent developments in superstring theory in the cosmological context, we examine a field theory which contains string networks with 3-way junctions. We perform numerical simulations of this model, identify the length scales of…

High Energy Physics - Theory · Physics 2009-11-11 Mark Hindmarsh , P. M. Saffin

At its very beginning, the universe is believed to have grown exponentially in size via the mechanism of inflation. The almost scale-invariant density perturbation spectrum predicted by inflation is strongly supported by cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 David F. Chernoff , S. -H. Henry Tye

Cosmic strings are linear concentrations of energy that form whenever phase transitions in the early universe break axial symmetries as originally shown by Kibble. They are the result of frustrated order in the quantum fields responsible…

Astrophysics · Physics 2008-11-11 A. Achucarro , C. J. A. P. Martins

We perform the lattice simulation to estimate the axion dark matter abundance radiated from the global cosmic strings in the post-inflationary scenario. The independent numerical confirmation on the recently observed logarithmic growth in…

High Energy Physics - Phenomenology · Physics 2024-07-17 Heejoo Kim , Junghyeon Park , Minho Son

We consider the evolution of circular string loops in power law expanding universes represented by a spatially flat Friedman-Robertson-Walker metric with scale factor $a(t)\propto t^p$ where $t$ is the cosmic time and $p\geq 0$. Our main…

High Energy Physics - Theory · Physics 2009-10-22 A. L. Larsen , Minos Axenides

We describe the formalism of a quantitative analytic model for the evolution of realistic wiggly (as opposed to Goto-Nambu) cosmic strings. The model is particularly suited for describing the evolution of small-scale structure on string…

High Energy Physics - Phenomenology · Physics 2015-06-19 C. J. A. P. Martins , E. P. S. Shellard , J. P. P. Vieira

We report on the results of performing computational gravitational backreaction on cosmic string loops taken from a network simulation. The principal effect of backreaction is to smooth out small-scale structure on loops, which we…

General Relativity and Quantum Cosmology · Physics 2025-11-14 Jeremy M. Wachter , Ken D. Olum , Jose J. Blanco-Pillado , Vishnu R. Gade , Kirthivarsha Sivakumar

We present a method for the introduction of small-scale structure into strings constructed from products of rotation matrices. We use this method to illustrate a range of possibilities for the shape of cusps that depends on the properties…

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

There has been recent interest in the evolution and cosmological consequences of global axionic string networks, and in particular in the issue of whether or not these networks reach the scale-invariant scaling solution that is known to…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-03 C. J. A. P. Martins

We show that in generic no-scale models in string theory, the flat, expanding cosmological evolutions found at the quantum level can be attracted to a "quantum no-scale regime", where the no-scale structure is restored asymptotically. In…

High Energy Physics - Theory · Physics 2018-04-18 Thibaut Coudarchet , Claude Fleming , Herve Partouche

We discuss data analysis techniques that can be used in the search for gravitational wave bursts from cosmic strings. When data from multiple interferometers are available, we describe consistency checks that can be used to greatly reduce…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Xavier Siemens , Jolien Creighton , Irit Maor , Saikat Ray Majumder , Kipp Cannon , Jocelyn Read
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