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Related papers: Evidence for cosmological particle creation?

200 papers

A cosmological model with anisotropic dark energy is analyzed. The amount of deviation from isotropy of the equation of state of dark energy, the skewness \delta, generates an anisotropization of the large-scale geometry of the Universe,…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-28 L. Campanelli , P. Cea , G. L. Fogli , L. Tedesco

These lecture notes aim to provide an introduction to dark matter from the perspective of astrophysics/cosmology. We start with a rapid overview of cosmology, including the evolution of the Universe, its thermal history and structure…

High Energy Physics - Phenomenology · Physics 2022-01-26 Anne M. Green

The universe with adiabatic matter creation is considered. It is thought that the negative pressure caused by matter creation can play the role of a dark energy component, and drive the accelerating expansion of the universe. Using the Type…

Astrophysics · Physics 2015-06-24 Yuan Qiang , Tong-Jie Zhang , Ze-Long Yi

We review the current status of cosmological parameters, dark energy and large-scale structure, from a theoretical and observational perspective. We first present the basic cosmological parameters and discuss how they are measured with…

Astrophysics · Physics 2007-05-23 S. E. Deustua , R. Caldwell , P. Garnavich , L. Hui , A. Refregier

Non-conservation of dark matter can lead to late-time cosmic acceleration. This mechanism is known as the matter creation theory and this replaces the need of dark energy and modified gravity theories. We consider a two-fluid system…

General Relativity and Quantum Cosmology · Physics 2025-12-02 Sudip Halder , Jaume de Haro , Supriya Pan , Tapan Saha , Subenoy Chakraborty

The theoretical basis for the prediction of anisotropies in the cosmic microwave background is very well developed. Very low amplitude density and temperature perturbations produce small gravitational effects, leading to an anisotropy that…

Astrophysics · Physics 2007-05-23 E. L. Wright

Observations of the Cosmic Microwave background have provided many of the most powerful constraints we have on cosmology and events in the early universe. The spectrum and isotropy of CBR have long been a pillar of Big Bang models. The…

Astrophysics · Physics 2016-08-30 George F. Smoot

The blackbody radiation left over from the Big Bang has been transformed by the expansion of the Universe into the nearly isotropic 2.73K Cosmic Microwave Background. Tiny inhomogeneities in the early Universe left their imprint on the…

The Cosmic Microwave Background provides our most ancient image of the Universe and our best tool for studying its early evolution. Theories of high energy physics predict the formation of various types of topological defects in the very…

Astrophysics · Physics 2011-09-29 M. Cruz , N. Turok , P. Vielva , E. Martinez-Gonzalez , M. Hobson

We use observational data on the large scale structure (LSS) of the Universe measured over a wide range of scales from sub-galactic up to horizon scale and on the cosmic microwave background anisotropies to determine cosmological parameters…

Astrophysics · Physics 2011-07-19 R. Durrer , B. Novosyadlyj

Recent measurements of the Cosmic Microwave Background Anisotropy have provided evidence for the presence of oscillations in the angular power spectrum. These oscillations are a wonderful confirmation of the standard cosmological scenario…

Astrophysics · Physics 2007-05-23 Alessandro Melchiorri

Full suite of the present day Cosmic Microwave background (CMB) data, when combined with weak prior information on the Hubble constant and the age of the Universe, or the Large-Scale structure, provides strong indication for a non-zero…

Astrophysics · Physics 2007-05-23 D. Pogosyan , J. R. Bond , C. R. Contaldi

I review the present status of the Cosmic Microwave Background, with some emphasis on the current and future implications for particle physics. Conclusions are: gravitational instability in a dark matter dominated universe grew today's…

Astrophysics · Physics 2007-05-23 Douglas Scott

Anisotropies in the electromagnetic emission produced by dark matter annihilation or decay in the extragalactic sky are a recent tool in the quest for a particle dark matter evidence. We review the formalism to compute the two-point angular…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-28 Nicolao Fornengo , Marco Regis

We review some results of the past 12 years derived from optical and infrared photometry of Type Ia supernovae. A combination of optical and infrared photometry allows us to determine accurately the extinction along the line of sight. The…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-01 Kevin Krisciunas

The Cosmic Microwave Background (CMB), which permeates the entire Universe, is the radiation left over from just 380,000 years after the Big Bang. On very large scales, the CMB radiation field is smooth and isotropic, but the existence of…

The cosmic expansion history proceeds in broad terms from a radiation dominated epoch to matter domination to an accelerated, dark energy dominated epoch. We investigate whether intermittent periods of acceleration are possible in the early…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-21 Eric V. Linder , Tristan L. Smith

While low-z Type Ia supernovae are used to measure the present rate of expansion of the Universe, high-z Type Ia measure its variation due to the cosmic matter-energy content. Results from those determinations imply a low matter density…

Astrophysics · Physics 2007-05-23 P. Ruiz-Lapuente

The South Pole Telescope (SPT), Atacama Cosmology Telescope (ACT), and Wilkinson Microwave Anisotropy Probe (WMAP) have each reported measurements of the cosmic microwave background's (CMB) angular power spectrum which favor the existence…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Dan Hooper , Farinaldo S. Queiroz , Nickolay Y. Gnedin

We devise a measure n(r) to quantify a robust feature in the coherent cosmic perturbations, namely the narrowness of the first peak in the power spectrum of the Cosmic Microwave Background (CMB) anisotropy. A maximum-likelihood analysis…

Astrophysics · Physics 2007-05-23 Jiun-Huei Proty Wu