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We show that it is possible to construct a consistent model describing a current-carrying cosmic string endowed with torsion. The torsion contribution to the gravitational force and geodesics of a test-particle moving around the SCCS are…

High Energy Physics - Theory · Physics 2007-05-23 C. N. Ferreira , H. J. Mosquera-Cuesta , L. C. Garcia de Andrade

We revisit the physical properties of global and local monopoles and discuss their implications in the dynamics of monopole networks. In particular, we review the Velocity-dependent One-Scale (VOS) model for global and local monopoles and…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-26 Lara Sousa , Pedro P. Avelino

The evolution of cosmic string networks is an interesting dynamical problem. The equations governing these networks are classical and fully specified, but the length scale at which cosmic string loops form has been uncertain to tens of…

Astrophysics · Physics 2009-06-23 Joseph Polchinski

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 study the evolution of Abelian-Higgs string networks in large-scale numerical simulations in both a static and expanding background. We measure the properties of the network by tracing the motion of the string cores, for the first time…

High Energy Physics - Phenomenology · Physics 2009-11-07 J. N. Moore , E. P. S. Shellard , C. J. A. P. Martins

We extend the quantititative string evolution model of Martins and Shellard to superconducting strings by introducing a simple toy model for the evolution of the currents. This is based on the dynamics of a `superconducting correlation…

High Energy Physics - Phenomenology · Physics 2009-10-30 C. J. A. P. Martins , E. P. S. Shellard

We evolve the network of global strings in the matter-dominated universe by means of numerical simulations. The existence of the scaling solution is confirmed as in the radiation-dominated universe but the scaling parameter $\xi$ takes a…

High Energy Physics - Phenomenology · Physics 2009-12-30 Masahide Yamaguchi , Jun'ichi Yokoyama , M. Kawasaki

We consider the evolution of a network of strings in an expanding universe, allowing for the formation of junctions between strings of different tensions. By explicitly including, in the velocity-dependent evolution equations for the…

High Energy Physics - Phenomenology · Physics 2010-04-06 A. Avgoustidis , E. J. Copeland

Cosmic strings are a type of cosmic defect formed by a symmetry-breaking phase transition in the early universe. Individual strings would have gathered to build a network, and their dynamical motion would induce scalar--, vector-- and…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-07 Kouichirou Horiguchi , Kiyotomo Ichiki , Naoshi Sugiyama

We make use of the formalism described in a previous paper [Martins {\it et al.} Phys. Rev. D90 (2014) 043518] to address general features of wiggly cosmic string evolution. In particular, we highlight the important role played by poorly…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-21 J. P. P. Vieira , C. J. A. P. Martins , E. P. S. Shellard

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 continue a comprehensive numerical study of semilocal string networks and their cosmological evolution. These can be thought of as hybrid networks comprised of (non-topological) string segments, whose core structure is similar to that of…

High Energy Physics - Phenomenology · Physics 2017-08-02 A. Lopez-Eiguren , J. Urrestilla , A. Achúcarro , A. Avgoustidis , C. J. A. P. Martins

In this work, the current stability is discussed for cosmic strings with the bosonic superconductivity. A non-vanishing curvature of string generally induce the quantum instability of the current-carrying particle. Its decay rates are…

High Energy Physics - Phenomenology · Physics 2023-02-15 Yoshihiko Abe , Yu Hamada , Kota Saji , Koichi Yoshioka

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 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

We consider an alternative approach for the computation of the stochastic gravitational wave background generated by small loops produced throughout the cosmological evolution of cosmic string networks and use it to derive an analytical…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-05 L. Sousa , P. P. Avelino

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

We use the velocity-dependent one-scale model by Martins & Shellard to investigate the evolution of a GUT long cosmic string network in arbitrary Friedmann-Lemaitre models. Four representative models are used to show that in general there…

Astrophysics · Physics 2009-10-30 Carsten van de Bruck

We investigate the properties of global cosmic string networks as a function of the ratio of string tension to Goldstone-field coupling, and as a function of the Hubble damping strength. Our results show unambiguously that the string…

High Energy Physics - Phenomenology · Physics 2020-06-17 Vincent B. Klaer , Guy D. Moore

Semilocal strings -- a particular limit of electroweak strings -- are an interesting example of a stable non-topological defect whose properties resemble those of their topological cousins, the Abrikosov-Nielsen-Olesen vortices. There is,…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 A. Achucarro , A. Avgoustidis , A. Lopez-Eiguren , C. J. A. P. Martins , J. Urrestilla