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Related papers: Extracting Primordial Density Fluctuations

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First the fluctuation energy is derived from the adiabatic random fluctuations due to the second-order perturbation theory, and the evolutionary relation for it is expressed in the form of rho_f = rho_f (rho), where rho and rho_f are the…

General Relativity and Quantum Cosmology · Physics 2017-09-12 Kenji Tomita

There is a puzzling contradiction: direct observations favor a low-mass-density universe ($0.2\le\Omega_m\le0.6$), but the only model which fits universe structure over more than three orders of magnitude in distance scale has a mix of hot…

High Energy Physics - Phenomenology · Physics 2007-05-23 David O. Caldwell

The observed dark matter abundance in the Universe can be explained with non-thermal, heavy dark matter models. In order for dark matter to still be present today, its lifetime has to far exceed the age of the Universe. In these scenarios,…

High Energy Astrophysical Phenomena · Physics 2021-07-27 Minjin Jeong

We show how, by considering the cumulative effect of tiny quantum gravitational fluctuations over very large distances, it may be possible to: ($a$) reconcile nucleosynthesis bounds on the density parameter of the Universe with the…

General Relativity and Quantum Cosmology · Physics 2009-10-22 T. Goldman , J. Pérez-Mercader , Fred Cooper , Michael Martin Nieto

We investigate a set of cosmological models for which the primordial power spectrum has a large-scale power deficit. The standard power-law spectrum is subject to long-wavelength modifications described by some new parameters, resulting in…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-13 Sandro D. P. Vitenti , Patrick Peter , Antony Valentini

Cosmological consequences of a coupling between massive neutrinos and dark energy are investigated. In such models, the neutrino mass is a function of a scalar field, which plays the role of dark energy. The background evolution, as well as…

Astrophysics · Physics 2010-04-06 A. W. Brookfield , C. van de Bruck , D. F. Mota , D. Tocchini-Valentini

Among the few ways that allow or could allow us to probe the early Universe from the observation of a flux of primordial particles, there is one possibility which has been little studied: the observation today of high energy neutrinos which…

High Energy Physics - Phenomenology · Physics 2025-10-27 Nicolas Grimbaum Yamamoto , Thomas Hambye

I review some of the basic information on the Cosmic Neutrino Background momentum distribution. In particular, I discuss how present data from several cosmological observables such as Big Bang Nucleosynthesis, Cosmic Microwave Background…

Astrophysics · Physics 2007-05-23 G. Mangano

Recent results from short--baseline neutrino oscillation experiments and Cosmic Microwave Background anisotropy measurements suggest the presence of additional sterile neutrinos. In this paper we properly combine these data sets to derive…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Maria Archidiacono , Nicolao Fornengo , Carlo Giunti , Alessandro Melchiorri

The high precision measurements of the cosmic microwave background by the Planck survey yielded tight constraints on cosmological parameters and the statistics of the density fluctuations at the time of recombination. This provides the…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-19 Hans Boehringer , Gayoung Chon

Cosmology is living through fascinating times, where new observations from ground and space telescopes are questioning the established paradigm, the so-called Lambda Cold Dark Matter model. The particle nature of Dark Matter is severely…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-15 Juan Garcia-Bellido

The gravitino problem is revisited in the framework of cosmological models in which the primordial cosmic matter is described by a relativistic imperfect fluid. Dissipative effects (or bulk viscosity effects) arise owing to the different…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-03 L. Buoninfante , G. Lambiase

The Cosmic Neutrino Background (CNB) encodes a wealth of information, but has not yet been observed directly. To determine the prospects of detection and to study its information content, we reconstruct the phase-space distribution of local…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-29 Willem Elbers , Carlos S. Frenk , Adrian Jenkins , Baojiu Li , Silvia Pascoli , Jens Jasche , Guilhem Lavaux , Volker Springel

This contribution gives a brief overview of the theoretical ideas underlying our current understanding of the early Universe. Confronting the predictions of the early Universe models with cosmological observations, in particular of the…

High Energy Physics - Theory · Physics 2017-08-23 David Langlois

The massive neutrinos of the Cosmic Neutrino Background (C$\nu$B) are fundamental ingredients of the radiation-dominated early universe and are important non-relativistic probes of the large-scale structure formation in the late universe.…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-02 Christopher G. Tully , Gemma Zhang

One of the primary targets of current and future cosmological observations are light thermal relics of the hot big bang. Within the Standard Model of particle physics, an important thermal relic are cosmic neutrinos, while interesting…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-08 Benjamin Wallisch

As a test of the standard inflationary cosmology, which generically predicts nearly scale-invariant spectrum of primordial curvature fluctuations, we perform Markov-Chain Monte-Carlo analysis to search for possible modulations in the power…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-12 Kiyotomo Ichiki , Ryo Nagata , Jun'ichi Yokoyama

We consider the phenomenological implications of the violation of the Pauli exclusion principle for neutrinos, focusing on cosmological observables such as the spectrum of Cosmic Microwave Background anisotropies, Baryon Acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-02 P. F. de Salas , S. Gariazzo , M. Laveder , S. Pastor , O. Pisanti , N. Truong

A wide range of large scale observations hint towards possible modifications on the standard cosmological model which is based on a homogeneous and isotropic universe with a small cosmological constant and matter. These observations, also…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-21 Leandros Perivolaropoulos

The comparison of cosmic abundances of the light elements with the density of baryonic stars and gas in the universe today provides a critical test of big bang theory and a powerful probe of the nature of dark matter. A new technique allows…

Astrophysics · Physics 2009-09-25 Craig J. Hogan