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Related papers: Non-linear dynamics of cosmic strings with non-sca…

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We present a full characterization of the phase transition in U(1) scalar field theory and of the associated vortex string thermodynamics in 3D. We show that phase transitions in the string densities exist and measure their critical…

High Energy Physics - Phenomenology · Physics 2016-09-06 Nuno D. Antunes , Luis M. A. Bettencourt , Mark Hindmarsh

We present an extension of the velocity-dependent one-scale model for cosmic string evolution, which is suitable for describing the evolution of local and global monopole networks. We discuss the key dynamical features that need to be…

High Energy Physics - Phenomenology · Physics 2009-11-13 C. J. A. P. Martins , A. Achucarro

A cosmic string network created during an inflationary stage in the early Universe - here defined as i-string network - is expected to enter a transient stretching regime during inflation, in which its characteristic length is stretched to…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-19 G. S. F. Guedes , P. P. Avelino , L. Sousa

We consider the low-energy effective string action in four dimensions including the leading order-$\alpha'$ terms. An exact homogeneous solution is obtained. It represents a non-singular expanding cosmological model in which the tensor…

General Relativity and Quantum Cosmology · Physics 2014-11-17 A. A. Al-Nowaiser , Murat Özer , M. O. Taha

Cosmic string networks generate cosmological perturbations actively throughout the history of the universe. Thus, the string sourced anisotropy of the cosmic microwave background is not affected by Silk damping as much as the anisotropy…

Astrophysics · Physics 2010-04-15 Levon Pogosian , S. -H. Henry Tye , Ira Wasserman , Mark Wyman

Cosmic superstring loops within the galaxy microlens background point sources lying close to the observer-string line of sight. For suitable alignments, multiple paths coexist and the (achromatic) flux enhancement is a factor of two. We…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-11 Jolyon K. Bloomfield , David F. Chernoff

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

Nonlinear effects were observed in a forced vibrating string. The motion of the string becomes elliptic as the amplitude of the vibration increases. The fundamental resonance frequency depends on the amplitude of the vibration. At…

Physics Education · Physics 2007-05-23 Miguel C. Brito , Jorge Maia Alves , Joao M. Serra , Antonio Vallera

We study the cosmic microwave background temperature and polarisation spectra sourced by multi-tension cosmic superstring networks. First we obtain solutions for the characteristic length scales and velocities associated with the evolution…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Alkistis Pourtsidou , Anastasios Avgoustidis , Edmund J. Copeland , Levon Pogosian , Daniele A. Steer

The initial data of the gravitational field produced by a loop thick string is considered. We show that a thick loop is not a geodesic on the initial hypersurface, while a loop conical singularity is. This suggests that there is the ``{\it…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Kouji Nakamura

We calculate Wilson loops on boundaries of Lifshitz-like dual backgrounds with different scaling parameters, assuming existence of a field theory dual to string theory in the bulk. We consider scaling parameters to be variable quantities…

High Energy Physics - Theory · Physics 2009-09-19 Peter Koroteev , A. V. Zayakin

We solve numerically the Boltzmann equation describing the evolution of a cosmic string network which contains only loops. In Minkowski space time the equilibrium solution predicted by statistical mechanics is recovered, and we prove that…

Astrophysics · Physics 2009-10-31 Joao Magueijo , Haavard Sandvik , Daniele Steer

We compute analytically the small-scale temperature fluctuations of the cosmic microwave background from cosmic (super-)strings and study the dependence on the string intercommuting probability $P$. We develop an analytical model which…

Cosmic strings are predicted in many models beyond the Standard Model of particle physics. In models which admit strings, a network of strings will inevitably be formed in a phase transition in the early universe and will persist to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Robert H. Brandenberger

We show that stable local cosmic strings are a generic prediction of supersymmetric models where supersymmetry is broken at scales within a few orders of magnitude of the weak scale and is fed down to the observable sector by gauge…

High Energy Physics - Phenomenology · Physics 2009-10-30 Antonio Riotto

We study the cosmological dynamics of non-minimally coupled matter models using the Brown's variational approach to relativistic fluids in General Relativity. After decomposing the Ricci scalar into a bulk and a boundary term, we construct…

General Relativity and Quantum Cosmology · Physics 2025-12-22 Hala A. Ashi , Christian G. Boehmer , Antonio d'Alfonso del Sordo , Erik Jensko

We obtain a non-relativistic diffeomorphism invariant string action as a special limit of the Nambu-Goto action in an FLRW background. We use this action to study non-relativistic string dynamics in an expanding universe and construct an…

Astrophysics · Physics 2009-06-19 A. Avgoustidis , Joaquim Gomis

We consider the evolution of linear perturbations in models with a nonminimal coupling between dark matter and scalar field dark energy. Growth of matter inhomogeneities in two examples of such models proposed in the literature are…

Astrophysics · Physics 2009-11-11 Tomi Koivisto

We derive the equations governing the dynamics of cosmic strings in a flat anisotropic universe of Bianchi type I and study the evolution of simple cosmic string loop solutions. We show that the anisotropy of the background can have a…

Astrophysics · Physics 2009-11-07 P. P. Avelino , C. J. A. P. Martins

In determining the gravitational signal of cusps from a network of cosmic strings loops, a number of key parameters have to be assumed. These include the typical number of cusps per period of string oscillation and the typical values of the…

High Energy Physics - Theory · Physics 2021-04-07 Despoina Pazouli , Anastasios Avgoustidis , Edmund J. Copeland