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Related papers: Cosmic String Wakes in Scalar-Tensor Gravities

200 papers

Some of the phenomenological implications of string cosmological models are reviewed, with particular attention to the spectra of the tensor, scalar and vector modes of the geometry. A class of self-dual string cosmological models is…

High Energy Physics - Theory · Physics 2007-05-23 Massimo Giovannini

We have investigated the cosmological scenarios with a four dimensional effective action which is connected with multidimensional, supergravity and string theories. The solution for the scale factor is such that initially universe undergoes…

General Relativity and Quantum Cosmology · Physics 2014-11-17 A. A. Sen , S. Sen

String theory provides the only consistent framework so far that unifies all interactions including gravity. We discuss gravity and cosmology in string theory. Conventional notions from general relativity like geometry, topology etc. are…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Elias Kiritsis , Costas Kounnas

We review the existence, formation and properties of cosmic strings in string theory, the wide variety of observational techniques that are being employed to detect them, and the constraints that current observations impose on string theory…

High Energy Physics - Theory · Physics 2015-05-28 Edmund J. Copeland , Levon Pogosian , Tanmay Vachaspati

The Zeldovich approximation is applied to study the accretion of hot and cold dark matter onto moving long strings. It is assumed that such defects carry a substantial amount of small-scale structure, thereby acting gravitationally as a…

Astrophysics · Physics 2009-12-30 V. Zanchin , J. A. S. Lima , R. Brandenberger

I review a cosmological model based on string-inspired gravity with anomalies and torsion, which leads to a cosmology of running-vacuum-model (RVM) type. It is argued that such a model can lead to observable, in principle, deviations from…

General Relativity and Quantum Cosmology · Physics 2023-06-16 Nick E. Mavromatos

New physics beyond the Standard Model can give rise to stochastic gravitational-wave backgrounds, for example through cosmic strings. In this way, gravitational-wave searches with pulsar-timing arrays as well as existing and future laser…

General Relativity and Quantum Cosmology · Physics 2024-02-01 Astrid Eichhorn , Rafael R. Lino dos Santos , João Lucas Miqueleto

Cosmic strings are generic cosmological predictions of many extensions of the Standard Model of particle physics, such as a $U(1)^\prime$ symmetry breaking phase transition in the early universe or remnants of superstring theory. Unlike…

High Energy Physics - Phenomenology · Physics 2018-06-13 Yanou Cui , Marek Lewicki , David E. Morrissey , James D. Wells

Cosmic strings are topological defects thought to have formed early in the life of the universe. If such objects exist, a study of their interaction with black holes is of interest. The equations of motion of a cosmic string have the form…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Jean-Pierre De Villiers

Future observations of the large-scale structure have the potential to investigate cosmological models with a high degree of complexity, including the properties of gravity on large scales, the presence of a complicated dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-26 Robert Reischke , Alessio Spurio Mancini , Björn Malte Schäfer , Philipp M. Merkel

We describe the results of high-resolution numerical simulations of string-induced structure formation in open universes and those with a non-zero cosmological constant. For models with $\Gamma = \Omega h = 0.1 - 0.2$ and a cold dark matter…

Astrophysics · Physics 2008-11-26 P. P. Avelino , E. P. S. Shellard , J. H. P. Wu , B. Allen

Several extensions of General Relativity and high energy physics include scalar fields as extra degrees of freedom. In the search for predictions in the non-linear regime of cosmological evolution, the community makes use of numerical…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-04 Claudio Llinares , David Mota

Motivated in part by string theory, we consider the idea that the standard LambdaCDM cosmological model might be modified by the effect of a long-range scalar dark matter interaction. The variant of this widely-discussed notion considered…

High Energy Physics - Theory · Physics 2009-11-10 Steven S. Gubser , P. J. E. Peebles

Cosmic strings are linear concentrations of energy that may be formed at phase transitions in the very early universe. At one time they were thought to provide a possible origin for the density inhomogeneities from which galaxies eventually…

High Energy Physics - Theory · Physics 2009-11-11 A. -C. Davis , T. W. B. Kibble

We consider new cosmological solutions with a collapsing, an intermediate and an expanding phase. The boundary between the expanding (collapsing) phase and the intermediate phase is seen by comoving observers as a cosmological past (future)…

High Energy Physics - Theory · Physics 2009-11-07 L. Cornalba , Miguel S. Costa

Cosmic strings are predicted by many Standard Model extensions involving the cosmological breaking of a symmetry with nontrivial first homotopy group and represent a potential source of primordial gravitational waves (GWs). Present efforts…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-07 Pierre Auclair , Simone Blasi , Vedran Brdar , Kai Schmitz

The present acceleration of the Universe strongly indicated by recent observational data can be modeled in the scope of a scalar-tensor theory of gravity. We show that it is possible to determine the structure of this theory (the scalar…

General Relativity and Quantum Cosmology · Physics 2009-10-31 B. Boisseau , G. Esposito-Farese , D. Polarski , A. A. Starobinsky

We study new physical phenomena and constraints in generalized scalar--tensor theories of gravity with $\Phi$--dependent masses. We investigate a scenario (which can arise in string theories) with two types of $\Phi$--dependent masses which…

High Energy Physics - Phenomenology · Physics 2016-08-14 J. A. Casas , J. García--Bellido , M. Quiros

Cosmic strings are generically predicted in many extensions of the Standard Model of particle physics. We propose a new avenue for detecting cosmic strings through their effect on the filamentary structure in the cosmic web. Using…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-11 M. A. Fernandez , Simeon Bird , Yanou Cui

This article, written for Scolarpedia, provides a brief introduction into the subject of cosmic strings, together with a review of their main properties, cosmological evolution and observational signatures.

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Tanmay Vachaspati , Levon Pogosian , Daniele Steer