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Related papers: The General Primordial Cosmic Perturbation

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Prospects for testing the adiabaticity of the primordial cosmological perturbations using MAP and PLANCK are evaluated. The most general cosmological perturbation in a universe with just baryons, photons, neutrinos, and a cold dark matter…

Astrophysics · Physics 2009-10-31 Martin Bucher , Kavilan Moodley , Neil Turok

The most general homogeneous and isotropic statistical ensemble of linear scalar perturbations which are regular at early times, in a universe with only photons, baryons, neutrinos, and a cold dark matter (CDM) component, is described by a…

Astrophysics · Physics 2009-10-31 Martin Bucher , Kavilan Moodley , Neil Turok

The damping of primordial perturbations at small scales gives rise to distortions of the cosmic microwave background (CMB). Here, the dependence of the distortion on the different types of cosmological initial conditions is explored,…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-18 Jens Chluba , Daniel Grin

Current cosmological data are well-described by the Lambda-Cold Dark Matter ($\Lambda$CDM) model, which assumes adiabatic initial conditions for the primordial density perturbations. This agreement between data and theory enables strong…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-02 Matthew R. Buckley , Peizhi Du , Nicolas Fernandez , Mitchell J. Weikert

We obtain very stringent bounds on the possible cold dark matter, baryon and neutrino isocurvature contributions to the primordial fluctuations in the Universe, using recent cosmic microwave background and large scale structure data. In…

Astrophysics · Physics 2009-11-07 P. Crotty , J. Garcia-Bellido , J. Lesgourgues , A. Riazuelo

Generic models for the origin of structure predict a spectrum of initial fluctuations with a mixture of adiabatic and isocurvature perturbations. Using the observed anisotropies of the cosmic microwave backgound, the matter power spectra…

Astrophysics · Physics 2009-11-10 Maria Beltran , Juan Garcia-Bellido , Julien Lesgourgues , Alain Riazuelo

This paper presents a systematic treatment of the linear theory of scalar gravitational perturbations in the synchronous gauge and the conformal Newtonian (or longitudinal) gauge. It differs from others in the literature in that we give, in…

Astrophysics · Physics 2015-06-24 Chung-Pei Ma , Edmund Bertschinger

We present a systematic treatment of the initial conditions and evolution of cosmological perturbations in a universe containing photons, baryons, neutrinos, cold dark matter, and a scalar quintessence field. By formulating the evolution in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Gregor Schaefer

Using both cosmic microwave background and large scale structure data, we put stringent bounds on the possible cold dark matter, baryon and neutrino isocurvature contributions to primordial fluctuations in the Universe. Neglecting the…

Astrophysics · Physics 2007-05-23 Juan Garcia-Bellido

According to the standard models of particle physics and cosmology, there should be a background of cosmic neutrinos in the present Universe, similar to the cosmic microwave photon background. The weakness of the weak interactions renders…

High Energy Physics - Phenomenology · Physics 2013-05-27 Gary Steigman

The combination of detections of anisotropy in the Cosmic Microwave Background radiation and observations of the large-scale distribution of galaxies probes the primordial density fluctuations of the universe on spatial scales varying by…

Astrophysics · Physics 2008-11-26 Eric Gawiser , Joseph Silk

Primordial nucleosynthesis provides a probe of the universal abundance of baryons when the universe was only a few minutes old. Recent observations of anisotropy in the cosmic microwave background (CMB) probe the baryon abundance when the…

Astrophysics · Physics 2007-05-23 G. Steigman , J. P. Kneller , A. Zentner

We present cosmological perturbation theory in neutrinos probe interacting dark-energy models, and calculate cosmic microwave background anisotropies and matter power spectrum. In these models, the evolution of the mass of neutrinos is…

Astrophysics · Physics 2009-06-23 Kiyotomo Ichiki , Yong-Yeon Keum

Very different processes characterize the decoupling of neutrinos to form the cosmic neutrino background (C$\nu$B) and the much later decoupling of photons from thermal equilibrium to form the cosmic microwave background (CMB). The C$\nu$B…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-20 J. Richard Bond , George M. Fuller , Evan Grohs , Joel Meyers , Matthew James Wilson

We consider the perturbation dynamics for the cosmic baryon fluid and determine the corresponding power spectrum for a $\Lambda(t)$CDM model in which a cosmological term decays into dark matter linearly with the Hubble rate. The model is…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-30 R. F. vom Marttens , W. S. Hipólito-Ricaldi , W. Zimdahl

We present a systematic treatment of the initial conditions and evolution of cosmological perturbations in a universe containing photons, baryons, neutrinos, cold dark matter, and a scalar quintessence field. By formulating the evolution in…

Astrophysics · Physics 2008-11-26 Michael Doran , Christian M. Mueller , Gregor Schaefer , Christof Wetterich

Matter isocurvature perturbations are strictly constrained from cosmic microwave background observations. We study a sneutrino curvaton model where both cold dark matter (CDM)/baryon isocurvature perturbations are generated. In our model,…

High Energy Physics - Phenomenology · Physics 2015-06-22 Keisuke Harigaya , Taku Hayakawa , Masahiro Kawasaki , Shuichiro Yokoyama

We introduce a new family of primordial cosmological perturbations that are not described by traditional power spectra. At the linear level, these perturbations live in the kernel of the spatial Laplacian operator, and thus we call them…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-08 Niayesh Afshordi , Matthew C. Johnson

In the first part of this work, I review the theoretical framework of cosmological perturbation theory necessary to understand the generation and evolution of cosmic microwave background (CMB) anisotropies. Using analytical and numerical…

Astrophysics · Physics 2009-09-29 Roberto Trotta

Primordial magnetic fields and massive neutrinos can leave an interesting signal in the CMB temperature and polarization. We perform a systematic analysis of general perturbations in the radiation-dominated universe, accounting for any…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 J. Richard Shaw , Antony Lewis
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