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Related papers: Cosmic Strings in an Open Universe: Quantitative E…

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Cosmic strings, a hot subject in the 1980's and early 1990's, lost its appeal when it was found that it leads to inconsistencies in the power spectrum of the measured cosmic microwave background temperature anisotropies. However,…

High Energy Physics - Theory · Physics 2008-11-26 Mairi Sakellariadou

We present in detail the convolutional neural network used in our previous work to detect cosmic strings in cosmic microwave background (CMB) temperature anisotropy maps. By training this neural network on numerically generated CMB…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-15 Razvan Ciuca , Oscar F. Hernández , Michael Wolman

Cosmic strings with degrees of freedom beyond the standard Abrikosov-Nielsen-Olesen or Nambu-Goto strings are ubiquitous in field theory as well as in models with extra dimensions, such as string theoretic brane inflation scenarios. Here we…

High Energy Physics - Phenomenology · Physics 2015-06-03 M. F. Oliveira , A. Avgoustidis , C. J. A. P. Martins

We showed that the part of strings could be detected by optical method is only 20% from the total available amount of such objects, therefore the gravitational lensing method has to be "completed" by CMB one. We found the general structure…

Astrophysics · Physics 2009-11-13 O. S. Sazhina , M. V. Sazhin , V. N. Sementsov , M. Capaccioli , G. Longo , G. Riccio , G. D'Angelo

The predictions of the inflationary LCDM paradigm match today's high-precision measurements of the cosmic microwave background anisotropy extremely well. The same data put tight limits on other sources of anisotropy. Cosmic strings are a…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Cora Dvorkin , Mark Wyman , Wayne Hu

Using an analytical model for the string network we show that the kurtosis of cosmic microwave background (CMB) temperature gradient maps is a good statistic to distinguish between the cosmic string model and inflationary models of…

Astrophysics · Physics 2011-05-10 R. Moessner , L. Perivolaropoulos , R. Brandenberger

We describe a numerical simulation of the evolution of an $S_3$ cosmic string network which takes fully into account the non-commutative nature of the cosmic string fluxes and the topological obstructions which hinder strings from moving…

Astrophysics · Physics 2009-10-30 Patrick N. McGraw

We report on a current investigation of the anisotropy pattern induced by cosmic strings on the cosmic microwave background radiation (MBR). We have numerically evolved a network of cosmic strings from a redshift of $Z = 100$ to the present…

Astrophysics · Physics 2007-05-23 B. Allen , R. R. Caldwell , E. P. S. Shellard , A. Stebbins , S. Veeraraghavan

We investigate the evolution of infinite strings as a part of a complete cosmic string network in flat space. We perform a simulation of the network which uses functional forms for the string position and thus is exact to the limits of…

General Relativity and Quantum Cosmology · Physics 2013-05-29 Vitaly Vanchurin , Ken Olum , Alexander Vilenkin

We introduce a very early universe model based on the thermodynamics of a gas of closed strings in a background which is non-perturbative in $\alpha'$. Upon considering the fully $\alpha'$-corrected equations extended to include certain…

High Energy Physics - Theory · Physics 2021-03-04 Heliudson Bernardo , Robert Brandenberger , Guilherme Franzmann

Cosmic strings are predicted by many field-theory models, and may have been formed at a symmetry-breaking transition early in the history of the universe, such as that associated with grand unification. They could have important…

High Energy Physics - Theory · Physics 2010-05-07 Edmund J. Copeland , T. W. B. Kibble

We discuss and summarise the predictions of a model for the non-equilibrium evolution of a network of cosmic strings initially containing {\em only loops} and {\em no infinite strings}. The results are of interest given recent work…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. A. Steer

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

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

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

We study the formation and evolution of an interconnected string network in large-scale field-theory numerical simulations, both in flat spacetime and in expanding universe. The network consists of gauge U(1) strings of two different kinds…

High Energy Physics - Theory · Physics 2008-11-26 Jon Urrestilla , Alexander Vilenkin

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

We extend and develop our previous work on the evolution of a network of cosmic strings. The new treatment is based on an analysis of the probability distribution of the end-to-end distance of a randomly chosen segment of left-moving string…

High Energy Physics - Phenomenology · Physics 2016-09-01 Daren Austin , E. J. Copeland , T. W. B. Kibble

Cosmic strings, topological defects predicted by high-energy theories, may contribute to the late-time expansion of the Universe, effectively mimicking dynamical dark energy. We investigate four phenomenological extensions of the…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-06 Hanyu Cheng , Eleonora Di Valentino , Luca Visinelli

The Cosmic Microwave Background (CMB) bispectrum of the temperature anisotropies induced by a network of cosmic strings is derived for small angular scales, under the assumption that the principal cause of temperature fluctuations is the…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 Mark Hindmarsh , Christophe Ringeval , Teruaki Suyama