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Related papers: Comparison of Spectral Index Determinations

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We investigate the prior dependence of constraints on cosmic tensor perturbations. Commonly imposed is the strong prior of the single-field inflationary consistency equation, relating the tensor spectral index nT to the tensor-to-scalar…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-28 Marina Cortês , Andrew R. Liddle , David Parkinson

To test the primordial power spectra predicted by a double inflationary model with a break of amplitude $\Delta=3$ at a scale of $2\pi/k\approx 10 \hm$ and CDM as dominant matter content, we perform PM simulations with 128$^3$ particles on…

Astrophysics · Physics 2010-11-30 L. Amendola , S. Gottloeber , J. P. Muecket , V. Mueller

In inflationary models with minimal amount of gravity waves, the primordial power spectrum of density fluctuations, $A_S^2(k)$, together with the basic cosmological parameters, completely specify the predictions for the cosmic microwave…

Astrophysics · Physics 2009-10-31 Yun Wang , David N. Spergel , Michael A. Strauss

%The content of this replacement paper is identical to the original. %We have attempted to fix the postscript so that it will print out on %a larger number of printers. Using recent experimental limits on $\mu$ distortions from COBE FIRAS,…

Astrophysics · Physics 2009-10-22 Wayne Hu , Douglas Scott , Joseph Silk

Observed power spectrum of matter found in Papers I and II is compared with analytical power spectra. Spatially flat cold and mixed dark matter models with cosmological constant and open models are considered. The primordial power spectrum…

Astrophysics · Physics 2009-10-31 J. Einasto , M. Einasto , E. Tago , A. A. Starobinsky , F. Atrio-Barandela , V. M"uller , A. Knebe , R. Cen

The power spectrum (PS) of mass density fluctuations, in the range $0.05 \leq k \leq 0.2 \ihmpc$, is derived from the Mark III catalog of peculiar velocities of galaxies, independent of ``biasing". It is computed from the density field as…

Astrophysics · Physics 2016-08-30 Tsafrir Kolatt , Avishai Dekel

We implement and investigate a method for measuring departures from scale-invariance, both scale-dependent as well as scale-free, in the primordial power spectrum of density perturbations using cosmic microwave background (CMB) C_l data and…

Astrophysics · Physics 2009-11-11 Samuel Leach

Cosmological theories for the origin and evolution of structure in the Universe are highly predictive of the form of the angular power spectrum of cosmic microwave background fluctuations. We present new results from a comprehensive study…

Astrophysics · Physics 2007-05-23 Stephen Hancock , Graca Rocha

The primordial matter power spectrum quantifies fluctuations in the distribution of dark matter immediately following inflation. Over cosmic time, over-dense regions of the primordial density field grow and collapse into dark matter halos,…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-30 Daniel Gilman , Andrew Benson , Jo Bovy , Simon Birrer , Tommaso Treu , Anna Nierenberg

The shape of the primordial fluctuation spectrum is probed by cosmic microwave background fluctuations which measure density fluctuations at z~1000 on scales of hundreds of Mpc and from galaxy redshift surveys, which measure structure at…

Astrophysics · Physics 2014-10-13 Joseph Silk , Eric Gawiser

We calculate the power spectrum of metric fluctuations in inflationary cosmology starting with initial conditions which are imposed mode by mode when the wavelength equals some critical length $\ell_{_{\rm C}}$ corresponding to a new energy…

High Energy Physics - Theory · Physics 2009-11-10 Jerome Martin , R. H. Brandenberger

The combined analysis of the cosmic microwave background on large scales and Lyman-alpha forest on small scales provides a sufficiently long lever arm to obtain strong constraints on the slope and curvature of the power spectrum of…

Astrophysics · Physics 2009-11-10 Matteo Viel , Jochen Weller , Martin Haehnelt

Geometric characteristics of random fields are exploited to test the consistency of density perturbation model spectra with COBE data. These CMB maps are analyzed using the number of anisotropy hot spots and their boundary curvature. CMB…

Astrophysics · Physics 2008-02-03 Sergio Torres

We analyse the spectrum of energy density fluctuations of a dual supergravity model where the dilaton and the moduli are stabilized and sucessful inflation is achieved inside domain walls that separate different vacua of the theory.…

General Relativity and Quantum Cosmology · Physics 2009-10-31 M. C. Bento , O. Bertolami , N. J. Nunes

We present estimates of parameters which model the primordial density fluctuations using CMB data from the VSA, 1st year WMAP, CBI and ACBAR along with external priors from 2dF and the HST. Taken at face value there is significant evidence…

Astrophysics · Physics 2007-05-23 Richard A. Battye , the VSA Collaboration

When extracting cosmological information from power spectrum measurements, we must consider the impact of super-sample density fluctuations whose wavelengths are larger than the survey scale. These modes contribute to the mean density…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-03 Yin Li , Wayne Hu , Masahiro Takada

We study the power spectrum of the mass density perturbations in an inflation scenario that includes thermal dissipation. We show that the condition on which the thermal fluctuations dominate the primordial density perturbations can easily…

Astrophysics · Physics 2009-10-31 Wolung Lee , Li-Zhi Fang

We employ a pixel-based likelihood technique to estimate the angular power spectrum of the COBE Differential Microwave Radiometer (DMR) 4-year sky maps. The spectrum is consistent with a scale-invariant power-law form with a normalization,…

Astrophysics · Physics 2009-10-28 G. Hinshaw , A. J. Banday , C. L. Bennett , K. M. Gorski , A. Kogut , G. F. Smoot , E. L. Wright

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…

General Relativity and Quantum Cosmology · Physics 2011-08-11 Mauricio Bellini

We use statistical and topological quantities to test the COBE-DMR first year sky maps against the hypothesis that the observed temperature fluctuations reflect Gaussian initial density perturbations with random phases. Recent papers…

Astrophysics · Physics 2011-02-11 G. F. Smoot , L. Tenorio , A. J. Banday , A. Kogut , E. L. Wright , G. Hinshaw , C. Bennett