English
Related papers

Related papers: Cosmic Strings Collision in Cosmological Backgroun…

200 papers

We investigate the characteristic modifications in the evolving cosmological perturbations when dark energy interacts with dust-like matter, causing the latter's background energy density fall off with time faster than usual. Focusing in…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-06 Mohit Kumar Sharma , Sourav Sur

We study the dynamics of a cosmic string loop captured by a rotating black hole, ignoring string reconnections. A loop is numerically evolved in Kerr spacetime, with the result that it turns into one or more growing or contracting…

General Relativity and Quantum Cosmology · Physics 2023-06-28 Heling Deng , Andrei Gruzinov , Yuri Levin , Alexander Vilenkin

The interaction of a cosmic string and a maximally charged dilatonic black hole is studied in the low-velocity limit. In particular, the string-black hole scattering at a low velocity is investigated.

General Relativity and Quantum Cosmology · Physics 2014-11-17 Kiyoshi Shiraishi

Cosmological constraints on moduli, whose coupling to matter is stronger than Planck mass suppressed coupling, are derived. In particular, moduli are considered to be produced by oscillating loops of cosmic strings and constraints are…

High Energy Physics - Phenomenology · Physics 2010-11-08 Eray Sabancilar

The merging rate of cosmic structures is computed, relying on the Ansatz that they can be predicted in the initial linear density field from the coalescence of critical points with increasing smoothing scale, used here as a proxy for cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-28 Corentin Cadiou , Christophe Pichon , Sandrine Codis , Marcello Musso , Dmitri Pogosyan , Yohan Dubois , Jean-François Cardoso , Simon Prunet

We perform a new and accurate study of the dependence on cosmological parameters of structure formation with local cosmic strings. The crucial new ingredients are the inclusion of the effects of gravitational backreaction on the evolution…

Astrophysics · Physics 2009-10-31 E. J. Copeland , Joao Magueijo , D. A. Steer

We examine the effects of cosmic strings on structure formation and on the ionization history of the universe. While Gaussian perturbations from inflation are known to provide the dominant contribution to the large scale structure of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Benjamin Shlaer , Alexander Vilenkin , Abraham Loeb

We perform numerical simulations of cosmic necklaces (systems of monopoles connected to two strings each) and investigate the conditions under which monopoles annihilate. When the total monopole energy is large compared to the string…

Astrophysics · Physics 2009-10-31 Xavier Siemens , Xavier Martin , Ken D. Olum

In models for hadron collisions based on string hadronization, the strings are usually treated as independent, allowing no interaction between the confined colour fields. In studies of nucleus collisions it has been suggested that strings…

High Energy Physics - Phenomenology · Physics 2015-02-16 Christian Bierlich , Gösta Gustafson , Leif Lönnblad , Andrey Tarasov

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

This paper explores the phenomenon of particle creation associated with cosmic strings in de Sitter spacetime, a model that represents the universe exponential expansion. We examine how the presence of cosmic strings in a de Sitter…

General Relativity and Quantum Cosmology · Physics 2025-06-10 Bilgehan Baris Oner , Ozlem Yesiltas

We constrain the cosmological density of cosmic string loops using two observational signatures -- gravitational microlensing and the Kaiser-Stebbins effect. Photometry from RXTE and CoRoT space missions and pulsar timing from Parkes Pulsar…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-22 M. S. Pshirkov , A. V. Tuntsov

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

In cosmological models where local cosmic strings are formed at the end of a period of inflation, the perturbations are seeded both by the defects and by the quantum fluctuations. In a subset of these models, for example those based on…

Astrophysics · Physics 2009-10-30 Carlo Contaldi , Mark Hindmarsh , Joao Magueijo

Cosmic strings, if they exist, source nonlinear and non-Gaussian perturbations all the way back to the time of equal matter and radiation (and earlier). Here, we compute the mass function of halos seeded by a scaling distribution of cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-16 Hao Jiao , Robert Brandenberger , Alexandre Refregier

We investigate the cosmological and astrophysical constraints on superconducting cosmic strings (SCSs). SCS loops emit strong bursts of electromagnetic waves, which might affect various cosmological and astrophysical observations. We take…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Koichi Miyamoto , Kazunori Nakayama

We study the deformation of a long cosmic string by a nearby rotating black hole. We examine whether the deformation of a cosmic string, induced by the gravitational field of a Kerr black hole, may lead to the formation of a loop of cosmic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Florian Dubath , Mairi Sakellariadou , Claude Michel Viallet

We develop the general formalism for joining, splitting and interconnection of closed and open strings. As an application, we study examples of fundamental cosmic string collisions leading to gravitational collapse. We find that the…

High Energy Physics - Theory · Physics 2009-11-11 R. Iengo , J. Russo

We discuss formation of cosmic strings associated with a spontaneously broken approximate $U(1)$ symmetry by performing classical field-theoretical simulations. An original $U(1)$ symmetry is explicitly broken down to its subgroup $Z_N$…

High Energy Physics - Phenomenology · Physics 2024-10-11 Kohei Fujikura , Mairi Sakellariadou , Michiru Uwabo-Niibo , Masahide Yamaguchi

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