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相关论文: Temperature Fluctuation and an Expected Limit of H…

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The cosmic microwave background (CMB) monopole temperature evolves with the inverse of the cosmological scale factor, independent of many cosmological assumptions. With sufficient sensitivity, real-time cosmological observations could thus…

宇宙学与河外天体物理 · 物理学 2020-05-14 Maximilian H. Abitbol , J. Colin Hill , Jens Chluba

The Cosmic Microwave Background radiation is a fundamental prediction of Hot Big Bang cosmology. The temperature of its black-body spectrum has been measured at the present time, $T_{\rm CMBR,0}$ = 2.726$\pm$ 0.010 K, and is predicted to…

天体物理学 · 物理学 2016-03-23 R. Srianand , Patrick Petitjean , Cedric Ledoux

A second-order expansion for the quantum fluctuations of the matter field was considered in the framework of the warm inflation scenario. The friction and Hubble parameters were expended by means of a semiclassical approach. The…

广义相对论与量子宇宙学 · 物理学 2014-11-17 Mauricio Bellini

The temperature at the end of reheating and the length of this cosmological phase can be bound to the inflationary observables if one considers the cosmological evolution from the time of Hubble crossing until today. There are many examples…

宇宙学与河外天体物理 · 物理学 2015-09-30 Rodolfo C. de Freitas , Sergio V. B. Gonçalves

We study the Hubble parameter $H(z)$ in perturbed Friedmann universe and obtain an expression of the perturbed Hubble parameter $H(z,\textbf{n})$. We derive the Hubble parameter power spectrum by using the initial spectrum during inflation…

宇宙学与河外天体物理 · 物理学 2015-06-19 Xi-Bin Li , Hao-Feng Qin , Zhi-Song Zhang , Tong-Jie Zhang

We calculate the expected angular power spectrum of the temperature fluctuations in the microwave background radiation (MBR) generated in the quasi-steady state cosmology (QSSC). The paper begins with a brief description of how the…

天体物理学 · 物理学 2009-11-07 J. V. Narlikar , R. G. Vishwakarma , Amir Hajian , Tarun Souradeep , G. Burbidge , F. Hoyle

A second-order expansion for the quantum fluctuations of the matter field was considered in the framemork of the warm inflation scenario. The friction and Hubble parameters were expanded by means of a semiclassical approach. The…

广义相对论与量子宇宙学 · 物理学 2007-05-23 Mauricio Bellini

Fluctuations in the cosmic microwave background (CMB) temperature are being studied with ever increasing precision. Two competing types of theories might describe the origins of these fluctuations: ``inflation'' and ``defects''. Here we…

天体物理学 · 物理学 2010-04-08 Andreas Albrecht , David Coulson , Pedro Ferreira , Joao Magueijo

Forthcoming cosmic microwave background experiments (CMB) will provide precise new tests of structure-formation theories. The geometry of the Universe may be determined robustly, and the classical cosmological parameters, such as the…

天体物理学 · 物理学 2007-05-23 Marc Kamionkowski

Inflationary cosmology predicts that the particle horizon should be generically much bigger than the present-day Hubble radius, $1/H_0$. This implies a special regime of super-Hubble scale energy density fluctuations imprinted on the cosmic…

天体物理学 · 物理学 2009-10-30 Arjun Berera , Li-Zhi Fang , Gary Hinshaw

We investigate the stochasticity in temperature fluctuations in the cosmic microwave background (CMB) radiation data from {\it Wilkinson Microwave Anisotropy Probe}. We show that the angular fluctuations of the temperature is a Markov…

The cosmic microwave background temperature is a cornerstone astrophysical observable. Its present value is tightly constrained, but its redshift dependence, which can now be determined until redshift $z\sim6.34$, is also an important probe…

宇宙学与河外天体物理 · 物理学 2022-11-23 L. Gelo , C. J. A. P. Martins , N. Quevedo , A. M. M. Vieira

Primordial gravitational waves are created during the de Sitter phase of an exponentially-expanding (inflationary) universe, due to quantum zero-point vacuum fluctuations. These waves produce fluctuations in the temperature of the Cosmic…

天体物理学 · 物理学 2022-09-07 Bruce Allen , Robert Caldwell , Scott Koranda

In a recently proposed approach to testing models of inflation by Cosmic Microwave Background (CMB) radiation the reheating temperature is directly expressed in terms of the CMB observables. Its model independent bounds translate in a given…

高能物理 - 唯象学 · 物理学 2026-04-21 Michał Marciniak , Marek Olechowski , Stefan Pokorski

The thermodynamic and dynamical properties of a variable dark energy model with density scaling as rho_x \propto (1+z)^m, z being the redshift, are discussed following the outline of Jetzer et al. This kind of models are proven to lead to…

宇宙学与河外天体物理 · 物理学 2011-09-08 Philippe Jetzer , Crescenzo Tortora

A systematic approach is presented for using CMB observables and reheating temperature for discriminating between various models of inflation and certain freeze-in dark matter scenarios. It is applied to several classes of…

高能物理 - 唯象学 · 物理学 2025-11-26 Anish Ghoshal , Paweł Kozów , Marek Olechowski , Stefan Pokorski

It is shown that the fluctuation in the temperature of the cosmic microwave background in any direction may be evaluated as an integral involving scalar and dipole form factors, which incorporate all relevant information about acoustic…

天体物理学 · 物理学 2009-11-06 Steven Weinberg

The observed power spectrum of the cosmic microwave background (CMB) is consistent with inflationary cosmology, which predicts a nearly scale-invariant power spectrum of quantum fluctuations of the inflaton field as they exit the Hubble…

高能物理 - 理论 · 物理学 2007-05-23 Leonard Parker

The spectrum and statistics of the cosmic microwave background radiation (CMBR) are investigated under the hypothesis that scale invariance of the primordial density fluctuations should be promoted to full conformal invariance. As in the…

天体物理学 · 物理学 2008-11-26 I. Antoniadis , P. O. Mazur , E. Mottola

I consider the COBE data coarse-grained field that characterize the now observable universe for a model of warm inflation which takes into account the thermal coupled fluctuations of the scalar field with the thermal bath. The power…

广义相对论与量子宇宙学 · 物理学 2011-08-11 Mauricio Bellini
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