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Related papers: Multiple inflation and the WMAP 'glitches' II. Dat…

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Features in the primordial scalar power spectrum provide a possible roadway to describe the outliers at the low multipoles in the WMAP data. Apart from the CMB angular power spectrum, these features can also alter the matter power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-04 Dhiraj Kumar Hazra

We revisit the constraints on inflation models by using the current cosmological observations involving the latest local measurement of the Hubble constant ($H_{0} = 73.00\pm 1.75$ km s $^{-1}$ Mpc$^{-1}$). We constrain the primordial power…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-20 Rui-Yun Guo , Xin Zhang

[Abridged] A sharp cut-off in the primordial scalar power spectrum on large scales has been known to improve the fit to the cosmic microwave background (CMB) data when compared to the more standard, nearly scale invariant power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-11 H. V. Ragavendra , Debika Chowdhury , L. Sriramkumar

Measurements of CMB anisotropy and, more recently, polarization have played a very important role allowing precise determination of various parameters of the `standard' cosmological model. The expectation of the paradigm of inflation and…

Astrophysics · Physics 2008-11-26 Tarun Souradeep

We revisit the Cosmic Microwave Background (CMB) constraints on the spatial curvature of the Universe, assessing how they change when the curvature parameter and the primordial inflationary scalar spectrum are treated consistently within…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-01 Enrico Specogna , Tatevik Vardanyan , William Giarè , Eleonora Di Valentino

We find the best-fit cosmological parameters for a scenario of inflation with only the sufficient amount of accelerated expansion for the $\lambda\phi^4$ potential. While for the simplest scenario of chaotic inflation all observable…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-25 Erandy Ramirez , Dominik J. Schwarz

In a recent paper, we suggested that the density fluctuation spectra arising from power-law (or extended) inflation, which are tilted with respect to the Harrison--Zel'dovich spectrum, may provide an explanation for the excess large scale…

Astrophysics · Physics 2007-05-23 David H Lyth , Andrew A Liddle

We compute the power spectrum of curvature perturbations in stochastic inflation. This combines the distribution of first crossing times through the end-of-inflation surface, which has been previously studied, with the distribution of the…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-27 Kenta Ando , Vincent Vennin

In this addendum to Phys.Rev. D74 (2006) 023502, we present an update of cosmological constraints on single-field inflation in light of the Wilkinson Microwave Ansiotropy Probe satellite mission five-year results (WMAP5). We find that the…

Astrophysics · Physics 2008-11-26 William H. Kinney , Edward W. Kolb , Alessandro Melchiorri , Antonio Riotto

We constrain cosmological models where the primordial perturbations have both an adiabatic and a (possibly correlated) cold dark matter (CDM) or baryon isocurvature component. We use both a phenomenological approach, where the primordial…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-09 Jussi Valiviita , Matti Savelainen , Marianne Talvitie , Hannu Kurki-Suonio , Stanislav Rusak

In a class of recently proposed models, the early universe is strongly coupled and described holographically by a three-dimensional, weakly coupled, super-renormalizable quantum field theory. This scenario leads to a power spectrum of…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Richard Easther , Raphael Flauger , Paul McFadden , Kostas Skenderis

Heavy particles with masses much bigger than the inflationary Hubble scale $H_*$, can get non-adiabatically pair produced during inflation through their couplings to the inflaton. If such couplings give rise to time-dependent masses for the…

High Energy Physics - Phenomenology · Physics 2021-12-08 Jeong Han Kim , Soubhik Kumar , Adam Martin , Yuhsin Tsai

We emphasize that the estimation of cosmological parameters from cosmic microwave background (CMB) anisotropy data, such as the recent high resolution maps from BOOMERanG and MAXIMA-1, requires assumptions about the primordial spectra. The…

Astrophysics · Physics 2009-10-31 Jerome Martin , Alain Riazuelo , Dominik J. Schwarz

We consider Cosmic Microwave Background constraints on inflation models for which the primordial power spectrum is a mixture of perturbations generated by inflaton fluctuations and fluctuations in a curvaton field. If future experiments do…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-10 William H. Kinney , Azadeh Moradinezhad Dizgah , Antonio Riotto

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…

High Energy Physics - Theory · Physics 2009-05-13 Takeshi Kobayashi , Shinji Mukohyama

The conventional $\Lambda$CDM cosmological model supplemented by the inflation concept describes the Universe very well. However, there are still a few concerns: new Planck data impose constraints on the shape of the inflaton potential,…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-03 Branislav Vlahovic , Maxim Eingorn , Cosmin Ilie

Using the techniques of out-of-equilibrium field theory, we study the influence on the properties of cosmological perturbations generated during inflation on observable scales coming from fluctuations corresponding today to scales much…

High Energy Physics - Theory · Physics 2009-11-10 Sabino Matarrese , Marcello A. Musso , Antonio Riotto

Inflation creates large-scale cosmological density perturbations that are characterized by an isotropic, homogeneous, and Gaussian random distribution about a locally flat background. Even in a flat universe, the spatial curvature measured…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Matthew Kleban , Marjorie Schillo

We use the WMAP 7 data to place constraints on oscillations supplementing an almost scale-invariant primordial power spectrum. Such oscillations are predicted by a variety of models, some of which amount to assuming there is some…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 P. Daniel Meerburg , Ralph Wijers , Jan Pieter van der Schaar

Abbreviated: We highlight the remarkable evolution in the CMB power spectrum over the past few years, and in the cosmological parameters for minimal inflation models derived from it. Grand unified spectra (GUS) show pre-WMAP optimal…

Astrophysics · Physics 2015-06-24 J. R. Bond , C. R. Contaldi , D. Pogosyan
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