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Related papers: Cosmic-String-Seeded Structure Formation

200 papers

We study linear power spectra and formation of large scale structures in flat cosmological models with $\Lambda \ge 0$ and cold plus hot dark matter components (MLM). The hot component consists of massive neutrinos with cosmological density…

Astrophysics · Physics 2007-05-23 R. Valdarnini , T. Kahniashvili , B. Novosyadlyj

Spectra of the stochastic gravitational wave backgrounds from cosmic strings are calculated and compared with present and future experimental limits. Background spectra are calculated numerically for dimensionless string tensions G mu/c^2…

Astrophysics · Physics 2008-11-26 Matthew R. DePies , Craig J. Hogan

We study the distribution of dark matter in the nonlinear regime in a model in which the primordial fluctuations include, in addition to the dominant primordial Gaussian fluctuations generated by the standard $\Lambda CDM$ cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-24 Disrael Cunha , Joachim Harnois-Deraps , Robert Brandenberger , Adam Amara , Alexandre Refregier

We describe an attempt to reconstruct the initial conditions for the formation of cosmological large-scale structure. The power spectrum of the primordial fluctuations is affected by bias, nonlinear evolution and redshift-space distortions,…

Astrophysics · Physics 2015-06-24 J. A. Peacock , S. J. Dodds

Cosmic strings are one-dimensional topological defects which could have been formed in the early stages of our Universe. They triggered a lot of interest, mainly for their cosmological implications: they could offer an alternative to…

High Energy Physics - Theory · Physics 2009-11-11 Mairi Sakellariadou

We study the formation of cosmic strings by confining a stochastic magnetic field into flux tubes in a numerical simulation. We use overdamped evolution in a potential that is minimized when the flux through each face in the simulation…

High Energy Physics - Theory · Physics 2008-11-26 Jose J. Blanco-Pillado , Ken D. Olum , Alexander Vilenkin

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…

High Energy Physics - Phenomenology · Physics 2024-07-17 Heejoo Kim , Junghyeon Park , Minho Son

We use our model of the small scale structure on cosmic strings to develop further the result of Siemens, Olum, and Vilenkin that the gravitational radiation length scale on cosmic strings is smaller than the previously assumed $\Gamma G\mu…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Joseph Polchinski , Jorge V. Rocha

Dynamical dark energy has gained renewed interest due to recent theoretical and observational developments. In the present paper, we focus on a string-motivated dark energy set-up, and perform a detailed cosmological analysis of exponential…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-04 Sukannya Bhattacharya , Giulia Borghetto , Ameek Malhotra , Susha Parameswaran , Gianmassimo Tasinato , Ivonne Zavala

We describe cosmological simulation techniques and their application to studies of cosmic structure formation, with particular attention to recent hydrodynamic simulations of structure in the high redshift universe. Collisionless N-body…

Astrophysics · Physics 2008-02-03 David H. Weinberg , Neal Katz , Lars Hernquist

I review the standard paradigm for understanding the formation and evolution of cosmic structure, based on the gravitational instability of dark matter, but many variations on this basic theme are viable. Despite the great progress that has…

Astrophysics · Physics 2007-05-23 Peter Coles

We explore the possibility of solving the dark energy and the coincidence problems by postulating the massless sector of closed strings. This sector constitutes the gravitational multiplet of string theory and, when applied to…

High Energy Physics - Theory · Physics 2025-01-13 Hocheol Lee , Jeong-Hyuck Park , Liliana Velasco-Sevilla , Lu Yin

We simulate the anisotropy in the cosmic microwave background (CMB) induced by cosmic strings. By numerically evolving a network of cosmic strings we generate full-sky CMB temperature anisotropy maps. Based on $192$ maps, we compute the…

Astrophysics · Physics 2008-11-26 B. Allen , R. R. Caldwell , E. P. S. Shellard , A. Stebbins , S. Veeraraghavan

The nature of dark matter is increasingly constrained by cosmological data. In this paper, we examine the implications of the Cosmic Microwave Background anisotropy limits on the density of cold dark matter under different theoretical…

Astrophysics · Physics 2009-11-07 A. Melchiorri , J. Silk

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 evaluate the two point functions of the stress energy from the largest string simulations carried out so far. The two point functions are used to calculate the cosmic microwave background (CMB) and cold dark matter (CDM) power spectra…

Astrophysics · Physics 2007-05-23 Carlo R. Contaldi , Mark Hindmarsh , Joao Magueijo

Models of string cosmology predict a stochastic background of gravitational waves with a spectrum that is strongly tilted towards high frequencies. I give simple approximate expressions for spectral densities of the cosmic background which…

High Energy Physics - Theory · Physics 2008-02-03 Ram Brustein

Cosmic strings can arise in hidden sector models with a spontaneously broken Abelian symmetry group. We have studied the couplings of the Standard Model fields to these so-called dark strings in the companion paper. Here we survey the…

High Energy Physics - Phenomenology · Physics 2015-06-23 Andrew J. Long , Tanmay Vachaspati

Gravitational waves from cosmic strings are generated in the first fractions of a second after the Big Bang, potentially providing a unprecedented probe of the early universe. We discuss the key dynamical processes underlying calculations…

Astrophysics · Physics 2007-05-23 R. A. Battye , R. R. Caldwell , E. P. S. Shellard

The inability of primordial baryonic density fluctuations, as observed in the cosmic microwave background (CMB), to grow into the present day astronomical structures is well established, under Newtonian and Einsteinian gravity. It is hence…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-03 X. Hernandez , M. A. Jimenez