English
Related papers

Related papers: COBE-DMR-normalised Open Inflation, CDM Cosmogony

200 papers

The COBE detection of microwave anisotropies provides the best way of fixing the amplitude of cosmological fluctuations on the largest scales. We discuss the impact of this new, precise normalization and give fitting formulae for the…

Astrophysics · Physics 2009-08-18 Martin White , Douglas Scott

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

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…

Astrophysics · Physics 2015-06-24 Andrew R Liddle , David H Lyth

The cosmic curvature $\Omega_{K}$ is an important parameter related to the inflationary cosmology and the ultimate fate of the universe. In this work, we adopt the non-CMB observations to constrain $\Omega_{K}$ in the $\Lambda$CDM model and…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-12 Peng-Ju Wu , Xin Zhang

We supply fitting formulae enabling the normalization of slow-roll inflation models to the four-year COBE data. We fully include the effect of the gravitational wave modes, including the predicted relation of the amplitude of these modes to…

Astrophysics · Physics 2008-11-26 Emory F Bunn , Andrew R Liddle , Martin White

The past, present and future of cosmic microwave background (CMB) anisotropy research is discussed, with emphasis on the Boomerang and Maxima balloon experiments. These data are combined with large scale structure (LSS) information and high…

Although the currently favored cold dark matter plus cosmological constant model for structure formation assumes an n=1 scale-invariant initial power spectrum, most inflation models produce at least mild deviations from n=1. Because the…

Astrophysics · Physics 2009-11-07 James S. Bullock , Andrew R. Zentner

A problem with high central densities in dark halos has arisen in the context of LCDM cosmologies with scale-invariant initial power spectra. Although n=1 is often justified by appealing to the inflation scenario, inflationary models with…

Astrophysics · Physics 2008-11-26 Andrew R. Zentner , James S. Bullock

We present a general formalism for computing Cosmic Background Radiation (CBR) and density fluctuations in open models with stiff sources. We find analytic Green's functions for the linearized Einstein equations in the presence of stiff…

Astrophysics · Physics 2010-11-01 Ue-Li Pen , David N. Spergel

Properly interpreted data from nearby galaxies $(z\simeq 0.01)$ lead to $\Omega \simeq 0.082$. Data from farther away galaxies $(z\simeq 1)$ with type Ia supernovae to $\Omega =0.153$. Data to be expected from very high redshifted galaxies…

Astrophysics · Physics 2007-05-23 J. A. Gonzalo

We consider pure isocurvature cold dark matter models in the case of open and closed universe. We allow for a large spectral tilt and scan the 6-dimensional parameter space for the best fit to the COBE, Boomerang, and Maxima-1 data. Taking…

Astrophysics · Physics 2008-11-26 Kari Enqvist , Hannu Kurki-Suonio , Jussi Valiviita

The cosmic microwave background radiation allows us to measure both the geometry and topology of the universe. It has been argued that the COBE-DMR data already rule out models that are multiply connected on scales smaller than the particle…

Astrophysics · Physics 2009-10-31 Neil J. Cornish , David N. Spergel

In these lectures I review the standard hot big-bang cosmology, emphasizing its successes, its shortcomings, and its major challenge---a detailed understanding of the formation of structure in the Universe. I then discuss the motivations…

Astrophysics · Physics 2007-05-23 Michael S. Turner

We consider structure formation and CMB anisotropies in a closed universe, both with and without a cosmological constant. The CMB angular power spectrum and the matter transfer function are presented, along with a discussion of their…

Astrophysics · Physics 2009-08-18 Martin White , Douglas Scott

I review the basic theory of the cosmic microwave background anisotropies in adiabatic cold dark matter cosmologies. The latest observational results on the CMB power spectrum are consistent with the simplest inflationary models and…

Astrophysics · Physics 2009-09-25 G. Efstathiou

Observations of large scale structure (LSS) and the Cosmic Microwave Background (CMB) each place separate constraints on the values of cosmological parameters. We calculate a joint likelihood based on various CMB experiments and the IRAS…

Astrophysics · Physics 2007-05-23 Matthew Webster , S. L. Bridle , M. P. Hobson , A. N. Lasenby , Ofer Lahav , Graca Rocha

Recent cosmic microwave background (CMB) measurements over a large range of angular scales have become sensitive enough to provide interesting constraints on cosmological parameters within a restricted class of models. We use the CMB…

Astrophysics · Physics 2008-02-03 Charles H. Lineweaver , Domingos Barbosa

The sky-RMS is the simplest model-independent characterization of a cosmological anisotropy signal. The RMS temperature fluctuations determined from the $COBE$-DMR four-year sky maps are frequency independent, consistent with the hypothesis…

We discuss cosmological inference from galaxy surveys, the X-Ray Background (XRB) and the Cosmic Microwave Background (CMB). We assume a family of Cold Dark Matter (CDM) models in a spatially flat universe with an initially scale-invariant…

Astrophysics · Physics 2007-05-23 Ofer Lahav , Sarah L. Bridle

We discuss variants of Cold Dark Matter (CDM) dominated cosmological models that give good agreement with a range of observations. We consider models with hot dark matter, tilt, $\Omega < 1$, or a cosmological constant. We also discuss the…

Astrophysics · Physics 2007-05-23 Rachel S. Somerville , Joel R. Primack