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Related papers: Collapse of a Circular Loop of Cosmic String

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In this paper, we study the equation of circular loops with time-dependant tension in the BTZ black hole background. We obtain various cases where cosmic string loops finally collapse to form black holes. Also, we study effect of the BTZ…

High Energy Physics - Theory · Physics 2011-08-24 J. Sadeghi , H. M. Farahani , B. Pourhassan , S. M. Noorbakhsh

The metric around a wiggly cosmic string is calculated in the linear approximation of Brans-Dicke theory of gravitation. The equations of motion for relativistic and non-relativistic particles in this metric are obtained. Light propagation…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Andres Arazi , Claudio Simeone

We study the behaviour and consequences of cosmic string networks in contracting universes. They approximately behave during the collapse phase as a radiation fluids. Scaling solutions describing this are derived and tested against…

Astrophysics · Physics 2015-06-24 P. P. Avelino , C. J. A. P. Martins , C. Santos , E. P. S. Shellard

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 study the collapse of a self-gravitating thick shell of bosons coupled to a scalar radiation field. Due to the non-adiabaticity of the collapse, the shell (quantum) internal degrees of freedom absorb energy from the (classical)…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Roberto Casadio

We study cosmic strings in the complex symmetron model, a scalar-tensor theory with a spontaneously broken local $U(1)$ symmetry in low matter density regions. Using numerical simulations, we show that these strings preferentially attach to…

High Energy Physics - Phenomenology · Physics 2025-08-19 Ali Nezhadsafavi , Levon Pogosian

We report on the results of performing computational gravitational backreaction on cosmic string loops taken from a network simulation. The principal effect of backreaction is to smooth out small-scale structure on loops, which we…

General Relativity and Quantum Cosmology · Physics 2025-11-14 Jeremy M. Wachter , Ken D. Olum , Jose J. Blanco-Pillado , Vishnu R. Gade , Kirthivarsha Sivakumar

In this talk we discuss aspects of TeV-scale gravitational collapse to black holes and string balls and their subsequent evaporation. Special emphasis is placed on the interplay of the string/black hole correspondence principle. These ideas…

High Energy Physics - Phenomenology · Physics 2007-05-23 Luis A. Anchordoqui , Jonathan L. Feng , Haim Goldberg , Alfred D. Shapere

Observational effects of cosmic string loops depend on how loops are distributed in space. Chernoff \cite{Chernoff} has argued that loops can be gravitationally captured in galaxies and that for sufficiently small values of $G\mu$ their…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-22 Mudit Jain , Alexander Vilenkin

We present a solution to the vacuum Einstein Equations which represents a collapse of a gravitational wave in 5 dimensions. Depending on the focal length of the wave, the collapse results, either in a black string covered by a horizon, or…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alexander Feinstein

We have simulated large-amplitude standing waves on an Abelian-Higgs cosmic string in classical lattice field theory. The radiation rate falls exponentially with wavelength, as one would expect from the field profile around a gauge string.…

Astrophysics · Physics 2009-10-31 Ken D. Olum , J. J. Blanco-Pillado

We discuss data analysis techniques that can be used in the search for gravitational wave bursts from cosmic strings. When data from multiple interferometers are available, we describe consistency checks that can be used to greatly reduce…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Xavier Siemens , Jolien Creighton , Irit Maor , Saikat Ray Majumder , Kipp Cannon , Jocelyn Read

In this paper the collision of two cosmic string loops is studied. After collision junctions are formed and the loops are entangled. We show that after their formation the junctions start to unzip and the loops disentangle. This analysis…

High Energy Physics - Theory · Physics 2009-11-06 Hassan Firouzjahi , Johanna Karouby , Shahram Khosravi , Robert Brandenberger

We describe the detailed study and results of high-resolution numerical simulations of string-induced structure formation in open universes and those with a non-zero cosmological constant. The effect from small loops generated from the…

Astrophysics · Physics 2009-09-25 J. H. P. Wu , P. P. Avelino , E. P. S. Shellard , B. Allen

In theories with cosmic strings, a small fraction of string loops may collapse to form black holes. In this Letter, various constraints on such models involving black holes are considered. Hawking radiation from black holes, gamma and…

Astrophysics · Physics 2009-10-30 Jane H. MacGibbon , Robert H. Brandenberger , U. F. Wichoski

To understand the properties of a possible cosmic string network requires knowledge of the structures on long strings, which control the breaking off of smaller loops. These structures are influenced by backreaction due to gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-20 Ken W. Robbins , III , Ken D. Olum

The fraction of cosmic string loops which collapse to form black holes is estimated using a set of realistic loops generated by loop fragmentation. The smallest radius sphere into which each cosmic string loop may fit is obtained by…

General Relativity and Quantum Cosmology · Physics 2009-10-28 R. R. Caldwell , Paul Casper

The collisions of cosmic strings loops and the dynamics of junctions formations in expanding backgrounds are studied. The key parameter controlling the dynamics of junctions formation, the cosmic strings zipping and unzipping is the…

High Energy Physics - Theory · Physics 2015-03-13 Hassan Firouzjahi , Salomeh Khoeini-Moghaddam , Shahram Khosravi

Motivated by the recent claim for gravitational lensing by a cosmic string, we reinvestigate the probability of finding such an event with upcoming wide-field surveys. If an observed lensing event is suspected to be due to a string,…

Astrophysics · Physics 2009-11-07 Dragan Huterer , Tanmay Vachaspati

String-loop effects may generate very weak matter couplings for a (massless) dilaton. We examine limits on the shift of such a dilaton toward its present equilibrium value from big-bang nucleosynthesis and the binary pulsar. On the other…

High Energy Physics - Phenomenology · Physics 2011-05-23 C. E. Vayonakis