相关论文: Radiation constraints from cosmic strings

A full quantum description of global vortex strings is presented in the framework of a pure Higgs system with a broken global U(1) symmetry in 3+1D. An explicit expression for the string creation operator is obtained, both in terms of the…

In this work, we consider a network of cosmic strings to explain possible deviation from \Lambda CDM behaviour. We use different observational data to constrain the model and show that a small but non zero contribution from the string…

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…

Rotation angle of the plane of polarization of the distant galactic radio waves has been estimated in a string inspired axion-dilaton background. It is found that the axion,dual to the field strength of the second rank antisymmetric…

It is shown that the axion concentrated in electroweak strings which are consequently stabilized may produce a rotation of the polarization angle of radiation from extragalactic sources larger than that caused by a background field, and…

We compute fermion quantum corrections to the energy of cosmic strings. A number of rather technical tools is needed to formulate this correction and we employ isospin and gauge invariance to verify consistency of these tools. These…

We compute maps of CMB temperature fluctuations seeded by cosmic strings using high resolution simulations of cosmic strings in a Friedmann-Robertson-Walker universe. We create full-sky, 18-degree and 3-degree CMB maps, including the…

We investigate the evolution of the global string network in the radiation dominated universe by use of numerical simulations in 3+1 dimensions. We find that the global string network settles down to the scaling regime where the energy…

Understanding of the signatures of cosmic string networks is limited by a large uncertainty in the sizes at which cosmic string loops form. We review cosmic string network evolution, and the gravitational signatures, with emphasis on this…

We present a new formula for the rate at which cosmic strings lose energy into gravitational radiation, valid for all piecewise-linear cosmic string loops. At any time, such a loop is composed of $N$ straight segments, each of which has…

We perform the lattice simulation to estimate the axion dark matter abundance radiated from the global cosmic strings in the post-inflationary scenario. The independent numerical confirmation on the recently observed logarithmic growth in…

We study the impact of fragmentation on the cosmic string loop number density, using an approach inspired by the three-scale model and a Boltzmann equation. We build a new formulation designed to be more amenable to numerical resolution and…

The supporting worldsheet of a string, membrane, or other higher dimensional brane, is analysed in terms of its first, second, and third fundamental tensors, and its inner and outer curvature tensors. The dynamical equations governing the…

The effective string theory emerging from the bilocal approximation to the Method of Vacuum Correlators in gluodynamics is shown to be well described by the 4D theory of the massive Abelian Kalb-Ramond field interacting with the string,…

Cosmological evolution of axionic strings is investigated by numerically solving field equations of a complex scalar field in 3+1 dimensions. It is shown that the global strings relax to the scaling solution with a significantly smaller…

Cosmic strings are a type of cosmic defect formed by a symmetry-breaking phase transition in the early universe. Individual strings would have gathered to build a network, and their dynamical motion would induce scalar--, vector-- and…

The formalism for computing the gravitational power radiation from excitations on cosmic strings forming a junction is presented and applied to the simple case of co-planar strings at a junction when the excitations are generated along one…

The static stationary axially symmetric background ("infinite cosmic string") of the $D=4$ string theory provided with an axion charge is studied in the effective theory approach. The most general exact solution is constructed. It is found…

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…

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…