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Related papers: Structure Formation in the Early Universe

200 papers

Primordial chemistry began, at the recombination epoch, when the adiabatic expansion caused the temperature of the radiation to fall below 4000K. The chemistry of the early Universe involves the elements hydrogen, its isotope deuterium,…

Astrophysics · Physics 2009-10-31 Denis Puy

It is obtained that dark energy emerges from higher-derivative gravity with anon-linear terms proportional to $R^2$ and $R^3$ with $R$ being the Ricci scalar curvature. Interestingly, it is found that the universe begins with acceleration,…

Astrophysics · Physics 2008-11-26 S. K. Srivastava

The quantity and quality of cosmic structure observations have greatly accelerated in recent years. Further leaps forward will be facilitated by imminent projects, which will enable us to map the evolution of dark and baryonic matter…

The existence of an early matter-dominated epoch prior to the Big Bang Nucleosynthesis may lead to a scenario where the thermal dark matter cools faster than plasma before the radiation-dominated era begins. In the radiation-dominated…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-21 Avik Banerjee , Debtosh Chowdhury , Arpan Hait , Md Sariful Islam

We generalize dark matter production to a two-metric framework whereby the physical metric, which couples to the Standard Model (SM), is conformally and/or disformally related to the metric governing the gravitational dynamics. We show that…

High Energy Physics - Phenomenology · Physics 2021-02-03 Philippe Brax , Kunio Kaneta , Yann Mambrini , Mathias Pierre

A short introduction to structure formation is given, followed by a discussion of the possible characteristics of the initial perturbations assuming a generic inflationary origin. Observational data related to large-scale structure and the…

Astrophysics · Physics 2014-10-13 Pedro Viana

An approximate statistical description of the formation and evolution of structure of the universe based on the Zel'dovich theory of gravitational instability is proposed. It is found that the evolution of DM structure shows features of…

Astrophysics · Physics 2009-10-31 M. Demianski , A. Doroshkevich

This work discusses scalar-tensor theories of gravity, with a focus on the Brans-Dicke subclass, and one that also takes note of the latter's equivalence with $f(R)$ gravitation theories. A 1+3 covariant formalism is used in this case to…

General Relativity and Quantum Cosmology · Physics 2018-01-08 Joseph Ntahompagaze , Amare Abebe , Manasse R. Mbonye

The `Little Bangs' made in particle collider experiments reproduce the conditions in the Big Bang when the age of the Universe was a fraction of a second. It is thought that matter was generated, the structures in the Universe were formed…

Astrophysics · Physics 2009-09-11 John Ellis

During the evolution of density inhomogeneties in an $\Omega=1$, matter dominated universe, the typical density contrast changes from $\delta\simeq 10^{-4}$ to $\delta\simeq 10^2$. However, during the same time, the typical value of the…

General Relativity and Quantum Cosmology · Physics 2019-08-17 J. S. Bagla , T. Padmanabhan

Creation of Cold Dark Matter (CCDM), in the context of Einstein Field Equations, leads to a negative creation pressure, which can be used to explain the accelerated expansion of the Universe. Recently, it has been shown that the dynamics of…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-20 J. F. Jesus , F. Andrade-Oliveira

We study the statistical mechanics of the early radiation dominated universe in the context of a generalized uncertainty principle which supports the existence of a minimal length scale. Utilizing the resultant modified thermodynamical…

General Relativity and Quantum Cosmology · Physics 2016-01-22 B. Vakili , M. A. Gorji

There are significant discrepancies between observational evidence and the hierarchical galaxy formation theory with respect to the shape of dark matter halos, the correlation between galaxy characteristics, and galaxy evolutionary history.…

General Physics · Physics 2011-07-28 Daniel E. Friedmann

According to the standard model of cosmology, the early universe has been dominated by radiation or non-relativistic matter in several eras of its history. However, many cosmological calculations involving particle processes are commonly…

General Relativity and Quantum Cosmology · Physics 2018-03-12 Juho Lankinen , Iiro Vilja

Within the first 20 minutes of the evolution of the hot, dense, early Universe, astrophysically interesting abundances of deuterium, helium-3, helium-4, and lithium-7 were synthesized by the cosmic nuclear reactor. The primordial abundances…

Astrophysics · Physics 2007-05-23 Gary Steigman

Astronomical observations of recent years show that the universe at high redshifts about ten is densely populated by the early formed objects: bright galaxies, quasars, gamma-bursters, and contains a lot of metals and dust. Such rich early…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-16 A. D. Dolgov

The dark energy dominated warm dark matter (WDM) model is a promising alternative cosmological scenario. We explore large-scale structure formation in this paradigm. We do this in two different ways: with the halo model approach and with…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Aurel Schneider , Robert E. Smith , Andrea V. Maccio , Ben Moore

As is well known, structure formation in the Universe at times after decoupling can be described by hydrodynamic equations. These are shown here to be equivalent to a generalization of the stochastic Kardar--Parisi--Zhang equation with…

General Relativity and Quantum Cosmology · Physics 2009-10-28 J. F. Barbero G. , A. Dominguez , T. Goldman , J. Perez-Mercader

Models with dark energy decaying into dark matter have been proposed to solve the coincidence problem in cosmology. We study the effect of such coupling in the matter power spectrum. Due to the interaction, the growth of matter density…

Astrophysics · Physics 2008-11-26 G. Olivares , F. Atrio-Barandela , D. Pavon

This is the first paper of a series devoted to the study of the cosmological implications of the parallel mirror world with the same microphysics as the ordinary one, but having smaller temperature, with a limit set by the BBN constraints.…

Astrophysics · Physics 2008-11-26 P. Ciarcelluti