English
Related papers

Related papers: Scaling solutions for varying tension strings

200 papers

We discuss the cosmological evolution of cosmic strings with time-dependent tension. We show that, in the case that the tension changes as a power of time, the cosmic string network obeys the scaling solution: the characteristic scale of…

High Energy Physics - Phenomenology · Physics 2009-11-11 Masahide Yamaguchi

The charge-velocity-dependent one-scale model is an extension of the canonical velocity-dependent one-scale model which explicitly incorporates additional degrees of freedom on the string worldsheet, such as arbitrary currents and charges,…

High Energy Physics - Phenomenology · Physics 2025-06-27 F. C. N. Q. Pimenta , C. J. A. P. Martins

We investigate cosmological evolution and implications of cosmic strings with time-dependent tension. We derive basic equations of time development of the correlation length and the velocity of such strings, based on the one scale model.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kazuhide Ichikawa , Tomo Takahashi , Masahide Yamaguchi

Cosmic (super)strings offer promising ways to test ideas about the early universe and physics at high energies. While in field theory constructions their tension is usually assumed to be constant (or at most slowly-varying), this is often…

High Energy Physics - Phenomenology · Physics 2025-05-08 Filippo Revello , Gonzalo Villa

Cosmic string networks are the best motivated relics of cosmological phase transitions, being unavoidable in many physically plausible extensions of the Standard Model. Most studies, including those providing constraints from and forecasts…

High Energy Physics - Phenomenology · Physics 2024-06-07 F. C. N. Q. Pimenta , C. J. A. P. Martins

We continue our exploration of the wiggly generalisation of the Velocity-Dependent One Scale Model for cosmic strings, through the study of its allowed asymptotic scaling solutions. We extend the work of a previous paper [Almeida $\&$…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-09 A. Almeida , C. J. A. P. Martins

We provide a general overview of the velocity-dependent one-scale model for cosmic string evolution and discuss two further extensions to it. We introduce and justify a new ansatz for the momentum parameter $k$, and also incorporate the…

High Energy Physics - Phenomenology · Physics 2014-11-17 C. J. A. P. Martins , E. P. S. Shellard

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

It has recently been realised that strings with time-dependent tensions exhibit interesting dynamics; in particular, when the tension decreases loops of string can grow and possibly percolate. We extend previous analytic studies of strings…

High Energy Physics - Theory · Physics 2026-01-09 Hubert Lau Sze Chun , Joseph Conlon

We develop velocity-dependent models describing the evolution of string networks that involve several types of interacting strings, each with a different tension. These incorporate the formation of Y-type junctions with links stretching…

Astrophysics · Physics 2014-11-18 A. Avgoustidis , E. P. S. Shellard

Cosmic strings are topological defects arising in a variety of cosmological scenarios, as the Universe undergoes symmetry-breaking phase transitions, whose discovery would offer valuable insight into the high-energy physics that shaped the…

High Energy Physics - Phenomenology · Physics 2026-02-27 P. B. Barbosa , C. J. A. P. Martins

We apply a recently developed formalism to study the evolution of a current-carrying string network under the simple but generic assumption of a linear equation of state. We demonstrate that the existence of a scaling solution with…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-24 C. J. A. P. Martins , Patrick Peter , I. Yu. Rybak , E. P. S. Shellard

Understanding the evolution and cosmological consequences of topological defect networks requires a combination of analytic modeling and numerical simulations. The canonical analytic model for defect network evolution is the…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 J. R. C. C. C. Correia , C. J. A. P. Martins

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

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

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 string junctions and their influence on the evolution of cosmic superstring networks are studied in full detail. We review kinematic constraints for colliding strings in a Friedmann-Lema\^itre-Robertson-Walker background and…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-27 I. Yu. Rybak , A. Avgoustidis , C. J. A. P. Martins

Cosmic strings are topological defects possibly formed in the early Universe, which may be observable due to their gravitational effects on the cosmic microwave background radiation or gravitational wave experiments. To this effect it is…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-01 R. P. L. Azevedo , C. J. A. P. Martins

We study the behaviour of cosmic string networks in contracting universes, and discuss some of their possible consequences. We note that there is a fundamental time asymmetry between defect network evolution for an expanding universe and a…

Astrophysics · Physics 2009-11-07 P. P. Avelino , C. J. A. P. Martins , C. Santos , E. P. S. Shellard

We study the asymptotic scaling properties of domain wall networks with three different tensions in various cosmological epochs. We discuss the conditions under which a scale-invariant evolution of the network (which is well established for…

High Energy Physics - Phenomenology · Physics 2015-03-03 M. F. Oliveira , C. J. A. P. Martins
‹ Prev 1 2 3 10 Next ›