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相关论文: Density perturbations in warm inflation and COBE n…

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Warm inflation is an interesting possibility of describing the early universe, whose basic feature is the absence, at least in principle, of a preheating or reheating phase. Here we analyze the dynamics of warm inflation generalizing the…

广义相对论与量子宇宙学 · 物理学 2009-11-07 H. P. De Oliveira , S. E. Jorás

We analyse the implications for inflationary models of the cosmic microwave background (cmb) anisotropy measured by COBE. Vacuum fluctuations during inflation generate an adiabatic density perturbation, and also gravitational waves. The…

天体物理学 · 物理学 2009-10-22 David H Lyth , Andrew R Liddle

We make a detailed calculation of the amplitude of isocurvature perturbations arising from inflationary models in which the cold dark matter is represented by a scalar field which acquires perturbations during inflation. We use this to…

天体物理学 · 物理学 2009-10-31 Andrew R Liddle , Anupam Mazumdar

Spectra of density perturbations produced during chaotic inflation are calculated, taking both adiabatic and isocurvature modes into account in a class of scalar-tensor theories of gravity in which the dilaton is metrically coupled.…

广义相对论与量子宇宙学 · 物理学 2009-10-30 Takeshi Chiba , Naoshi Sugiyama , Jun'ichi Yokoyama

This is a review of the Cold Dark Matter model of structure formation, and its variants. The approach is largely from first principles, the main aim being to impart a basic understanding of the relevant theory with an eye to the likely…

天体物理学 · 物理学 2010-11-30 Andrew R Liddle , David H Lyth

Warm inflation is examined in a multi-field model. Solutions are obtained for expansion e-folds and scalar density perturbations. Nonequilibrium dynamics is restricted to a regime that is displaced only slightly from thermal equilibrium and…

高能物理 - 唯象学 · 物理学 2009-10-31 Arjun Berera

We investigate the phenomenology of warm inflation and present generic results about the evolution of the inflaton and radiation fields. The general conditions required for warm inflation to take place are derived and discussed. A…

天体物理学 · 物理学 2009-10-31 A. N. Taylor , A. Berera

Conditions are obtained for the existence of a warm inflationary attractor in the system of equations describing an inflaton coupled to radiation. These conditions restrict the temperature dependence of the dissipative terms and the size of…

天体物理学 · 物理学 2011-07-13 Ian G Moss , Chun Xiong

Probing correlations among short and long-wavelength cosmological fluctuations is known to be decisive for deepening the current understanding of inflation at the microphysical level. Spectral distortions of the CMB can be caused by…

宇宙学与河外天体物理 · 物理学 2016-12-14 Emanuela Dimastrogiovanni , Razieh Emami

We explore constraints on inflationary models employing data on large scale structure mainly from COBE temperature anisotropies and IRAS selected galaxy surveys, taking care not to apply linear perturbation theory to data in the non-linear…

天体物理学 · 物理学 2009-12-30 R. K. Schaefer , Q. Shafi

Recent large scale structure observations, including COBE, have prompted many authors to discuss modifications of the standard Cold Dark Matter model. Two of these, a tilted spectrum and a gravitational wave contribution to COBE, are at…

天体物理学 · 物理学 2015-06-24 Andrew R Liddle , David H Lyth

We investigate density perturbations generated through modulated reheating while inflation is driven by a conformally coupled scalar field. A large running of the spectral index is obtained, which reflects the basic nature of conformal…

高能物理 - 理论 · 物理学 2009-05-13 Takeshi Kobayashi , Shinji Mukohyama

Comparison of theobservedanisotropy with that predicted iadiabaticDM models suggest that much of thserved signal may be due to long wavelenh gravitational waves. In inflationary models this requires the generation of tensor fluctuations to…

高能物理 - 唯象学 · 物理学 2007-05-23 Lawrence M. Krauss

We derive a closed-form, analytical expression for the spectrum of long-wavelength density perturbations in inflationary models with two (or more) inflaton degrees of freedom that is valid in the slow-roll approximation. We illustrate…

天体物理学 · 物理学 2009-09-15 V. F. Mukhanov , Paul J. Steinhardt

Warm inflation, its different particle physics model implementations and the implications of dissipative particle production for its cosmology are reviewed. First, we briefly present the background dynamics of warm inflation and contrast it…

高能物理 - 唯象学 · 物理学 2023-03-01 Vahid Kamali , Meysam Motaharfar , Rudnei O. Ramos

Thermal fluctuations provide the main source of large scale density perturbations in warm inflationary models of the early universe. For the first time, general results are obtained for the power spectrum in the case when the friction…

宇宙学与河外天体物理 · 物理学 2010-04-28 Chris Graham , Ian G Moss

Inflation creates both scalar (density) and tensor (gravity wave) metric perturbations. We find that the tensor mode contribution to the CMB anisotropy on large-angular scales can only exceed that of the scalar mode in models where the…

天体物理学 · 物理学 2009-09-15 R. L. Davis , H. M. Hodges , G. F. Smoot , P. J. Steinhardt , M. S. Turner

We discuss the spectrum of scalar density perturbations from warm inflation when the friction coefficient $\Gamma$ in the inflaton equation is dependent on the inflaton field. The spectral index of scalar fluctuations depends on a new…

天体物理学 · 物理学 2009-11-10 Lisa M. H. Hall , Ian G. Moss , Arjun Berera

We propose a $\Lambda$-inflation model which explains a large fraction of the COBE signal by cosmic gravitational waves. The primordial density perturbations fulfil both the contraints of large-scale microwave background and galaxy cluster…

天体物理学 · 物理学 2011-07-19 V. N. Lukash , E. V. Mikheeva , V. Müller , A. M. Malinovsky

A brief account is given of large-scale structure modelling based on the assumption that the initial perturbations arise from inflation. A recap is made of the implications of inflation for large-scale structure; under the widely applicable…

天体物理学 · 物理学 2007-05-23 Andrew R Liddle
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