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We review the relevant 10+ parameters associated with inflation and matter content; the relation between LSS and primary and secondary CMB anisotropy probes; COBE constraints on energy injection; current anisotropy band-powers which…

Astrophysics · Physics 2009-10-30 J. Richard Bond , Andrew H. Jaffe

We use cosmic microwave background (CMB) and large-scale structure data to constrain cosmological models where the primordial perturbations have both an adiabatic and a cold dark matter (CDM) isocurvature component. We allow for a possible…

Astrophysics · Physics 2008-06-23 Hannu Kurki-Suonio , Vesa Muhonen , Jussi Valiviita

Generic models for the origin of structure predict a spectrum of initial fluctuations with a mixture of adiabatic and isocurvature perturbations. Using the observed anisotropies of the cosmic microwave backgound, the matter power spectra…

Astrophysics · Physics 2009-11-10 Maria Beltran , Juan Garcia-Bellido , Julien Lesgourgues , Alain Riazuelo

We analyse the efficiency of future large scale structure surveys to unveil the presence of scale dependent features in the primordial spectrum --resulting from cosmic inflation-- imprinted in the distribution of galaxies. Features may…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-04 Gonzalo A. Palma , Domenico Sapone , Spyros Sypsas

We examine the constraints cosmological observations can place on any trans-Planckian corrections to the primordial spectrum of perturbations underlying the anisotropies in the Cosmic Microwave Background. We focus on models of…

Astrophysics · Physics 2011-05-12 Richard Easther , William H Kinney , Hiranya Peiris

Different inflationary models predict oscillatory features in the primordial power spectrum. These can leave an imprint on both the cosmic microwave background (CMB) and the large-scale structure (LSS) of our Universe, that can be searched…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-15 Chenxiao Zeng , Ely D. Kovetz , Xuelei Chen , Yan Gong , Julian B. Muñoz , Marc Kamionkowski

The anisotropy of the cosmic microwave background radiation contains information about the contents and history of the universe. We report new limits on cosmological parameters derived from the angular power spectrum measured in the first…

One of the major predictions of inflation is the existence of a stochastic background of cosmological gravitational waves (GW). These gravitational waves can induce significant temperature anisotropies in the Cosmic Microwave Background…

Astrophysics · Physics 2009-11-07 Alessandro Melchiorri , Carolina Odman

The ability to test and constrain theories of cosmic inflation will advance substantially over the next decade. Key data sources include cosmic microwave background (CMB) measurements and observations of the distribution of matter at…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-13 Benedict Bahr-Kalus , David Parkinson , Richard Easther

We constrain the spectrum of primordial curvature perturbations by using recent Cosmic Microwave Background (CMB) and Large Scale Structure (LSS) data. Specifically, we consider CMB data from the COBE, Boomerang and Maxima experiments, the…

Astrophysics · Physics 2009-11-06 S. Hannestad , S. H. Hansen , F. L. Villante , A. J. S. Hamilton

Recently, the nine-year data release of the Wilkinson Microwave Anisotropy Probe (WMAP9) found that the inflationary models with the scalar spectral index n_s \geq 1 are excluded at about 5\sigma confidence level. In this paper, we set the…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-15 Hong Li , Jun-Qing Xia , Xinmin Zhang

Observations from the first flight of the Medium Scale Anisotropy Measurement (MSAM) are analyzed to place limits on Gaussian fluctuations in the Cosmic Microwave Background Radiation (CMBR). This instrument chops a 30\arcmin\ beam in a 3…

New measurements of galaxy clustering and background radiations provide improved constraints on the isotropy and homogeneity of the Universe on large scales. In particular, the angular distribution of radio sources and the X-Ray Background…

Astrophysics · Physics 2009-10-16 Kelvin K. S. Wu , Ofer Lahav , Martin J. Rees

An analysis of cosmological models in spatially flat Friedmann Universe with cosmic gravitational wave background and zero $\Lambda$-term is presented. The number of free parameters is equal to 5, they are $\sigma_8$, $n$, $\Omega_\nu$,…

Astrophysics · Physics 2009-10-31 E. V. Mikheeva , V. N. Lukash , N. A. Arkhipova , A. M. Malinovsky

A stochastic background of primordial gravitational waves may substantially contribute, via the Sachs--Wolfe effect, to the large--scale Cosmic Microwave Background (CMB) anisotropies recently detected by COBE. This implies a {\it bias} in…

High Energy Physics - Phenomenology · Physics 2011-07-19 F. Lucchin , S. Matarrese , S. Mollerach

We discuss the cosmological implications of the new constraints on the power spectrum of the Cosmic Microwave Background Anisotropy derived from a new high resolution analysis of the MAXIMA-1 measurement (Lee et al. 2001). The power…

We propose a new source for the cosmological density perturbation which is passive fluctuations of the inflaton driven dynamically by a colored quantum noise as a result of its coupling to other massive quantum fields. The created…

Astrophysics · Physics 2010-10-27 Chun-Hsien Wu , Kin-Wang Ng , Wolung Lee , Da-Shin Lee , Yeo-Yie Charng

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

Cosmic Microwave Background (CMB) anisotropies that result from quantum fluctuations during inflation are explored and the impact of their ``cosmic variance'' on the ability to use existing data to probe inflationary models is studied. We…

Astrophysics · Physics 2016-08-30 Martin White , Lawrence M. Krauss , Joseph Silk

We consider the primordial gravitational wave (GW) background in a class of spatially-flat inflationary cosmological models with cold dark matter (CDM), a cosmological constant, and a broken-scale-invariant (BSI) steplike primordial…

Astrophysics · Physics 2009-10-30 J. Lesgourgues , D. Polarski , A. A. Starobinsky