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Related papers: Effects of anisotropic dynamics on cosmic strings

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We discuss the main cosmological implications of considering string-loop effects and a potential for the dilaton in the lowest order string effective action. Our framework is based on the effective model arising from regarding homogeneous…

General Relativity and Quantum Cosmology · Physics 2009-10-28 M. C. Bento , O. Bertolami

We investigate the effect of wiggly cosmic strings on the cosmic microwave background radiation anisotropy and matter power spectrum by modifying the string network model used by Albrecht et al.. We employ the wiggly equation of state for…

Astrophysics · Physics 2016-08-25 Levon Pogosian , Tanmay Vachaspati

Global topological defects produce nonzero stress-energy throughout spacetime, and as a result can have observable gravitational influence on surrounding matter. Gravitational effects of global strings are used to place bounds on their…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Shane L. Larson , William A. Hiscock

A recently proposed mechanism for large-scale structure in string cosmology --based on massless axionic seeds-- is further analyzed and extended to the acoustic-peak region. Existence, structure, and normalization of the peaks turn out to…

Astrophysics · Physics 2009-10-31 A. Melchiorri , F. Vernizzi , R. Durrer , G. Veneziano

We investigate scaling and correlations of the energy and momentum in an evolving network of cosmic strings in Minkowski space. These quantities are of great interest, as they must be understood before accurate predictions for the power…

Astrophysics · Physics 2009-10-28 Graham R. Vincent , Mark Hindmarsh , Mairi Sakellariadou

We investigate the anisotropies of the stochastic gravitational-wave background (SGWB) produced by cosmic strings associated with the spontaneous U(1) symmetry breaking of Grand Unified Theory, which happens at the onset of inflation. The…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-21 Rong-Gen Cai , Zong-Kuan Guo , Jing Liu

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

The dynamics of closed cosmic strings in Peres background, using finite-difference method, has been considered. It is shown that motion of the strings is very complicated and its perform complex oscillations and deformed to form loops and…

High Energy Physics - Theory · Physics 2013-06-24 Sergey Roshchupkin , Alexey Zhovtan

We study cosmic Nielsen-Olesen strings in space-times with a positive cosmological constant. For the free cosmic string in a cylindrically symmetric space-time, we calculate the contribution of the cosmological constant to the angle…

General Relativity and Quantum Cosmology · Physics 2008-12-31 Sourav Bhattacharya , Amitabha Lahiri

We construct cosmological spacetimes with null Kasner-like singularities as purely gravitational solutions with no other background fields turned on. These can be recast as anisotropic plane-wave spacetimes by coordinate transformations. We…

High Energy Physics - Theory · Physics 2009-07-30 Kallingalthodi Madhu , K. Narayan

We consider the propagation of classical and quantum strings on cosmological space-times which interpolate from a collapsing phase to an expanding phase. We begin by considering the classical propagation of strings on space-times with…

High Energy Physics - Theory · Physics 2009-11-11 Andrew J. Tolley

We study the interaction of several types of static straight cosmic strings, including local strings, global strings, and bosonic superconducting strings with and without magnetic currents. First, we evaluate the interaction energy of two…

High Energy Physics - Phenomenology · Physics 2023-09-12 Kohei Fujikura , Siyao Li , Masahide Yamaguchi

An implicit, fully characteristic, numerical scheme for solving the field equations of a cosmic string coupled to gravity is described. The inclusion of null infinity as part of the numerical grid allows us to apply suitable boundary…

General Relativity and Quantum Cosmology · Physics 2009-10-31 U. Sperhake , K. R. P. Sjodin , J. A. Vickers

The cosmic string theory for cosmological fluctuations is a good example of healthy scientific progress in cosmology. It is a well defined physically motivated model that has been tested by cosmological observations and has been ruled out…

Astrophysics · Physics 2009-11-10 L. Perivolaropoulos

The unique, conical spacetime created by cosmic strings brings about distinctive gravitational lensing phenomena. The variety of these distinctive phenomena is increased when the strings have non-trivial mutual interactions. In particular,…

High Energy Physics - Theory · Physics 2013-05-29 Benjamin Shlaer , Mark Wyman

At early stages the dynamics of cosmic string networks is expected to be influenced by an excessive production of small loops at the scales of initial conditions l_{min}. To understand the late time behavior we propose a very simple…

High Energy Physics - Theory · Physics 2014-11-21 Vitaly Vanchurin

We formulate an analytic method to study the discontinuities in superconducting cosmic strings. Equations of discontinuities and conditions of their existence are derived from the intrinsic and extrinsic equations of motion. It is the…

High Energy Physics - Theory · Physics 2014-08-05 Ernst Trojan

We briefly review the equations of motion and the space-time interval due to the nonlinear cosmic string that have been derived in ref. [3] for the first time. The different types of isotropic and nonisotropic geodesic lines in the…

General Physics · Physics 2007-05-23 L. M. Chechin , T. B. Omarov

Cosmic strings in realistic particle physics models have fermion zero modes in the string core. Such zero modes change the underlying cosmology; for example, the string can carry a current. We consider the stability of fermion zero modes to…

High Energy Physics - Phenomenology · Physics 2016-11-03 Anne-Christine Davis , Stephen C. Davis , Warren B. Perkins

Progress in string theory has resulted in a whole landscape of vacua solutions.In this talk I describe a proposal for exploring the cosmological implications of the landscape, based on the dynamics of the wavefunction of the universe…

High Energy Physics - Phenomenology · Physics 2009-11-11 Laura Mersini-Houghton