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Related papers: Testing Models for Structure Formation

200 papers

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

We consider cosmological applications of galaxy number density correlations to be inferred from future deep and wide multi-band optical surveys. We mostly focus on very large scales as a probe of possible features in the primordial power…

Astrophysics · Physics 2009-11-13 Hu Zhan , Lloyd Knox , J. Anthony Tyson , Vera Margoniner

The simplest realizations of the new inflationary scenario typically give rise to primordial density fluctuations which deviate logarithmically from the scale free Harrison - Zeldovich spectrum. We consider a number of such examples and, in…

High Energy Physics - Phenomenology · Physics 2011-05-12 R. K. Schaefer , Q. Shafi

Theoretical models for structure formation with Gaussian initial fluctuations have been worked out in considerable detail and compared with observations on various scales. It is on nonlinear scales $\lsim 10 \ h^{-1}\ {\rm Mpc}$ that the…

Astrophysics · Physics 2007-05-23 Joel R. Primack

We consider constraints on the structure formation model based on non-Gaussian fluctuations generated during inflation, which have $\chi_m^2$ distributions. Using three data sets, the abundance of the clusters at $z=0$, moderate $z$ and the…

Astrophysics · Physics 2009-10-31 Kazuya Koyama , Jiro Soda , Atsushi Taruya

We address the possibility of bounding the spectral index $n$ of primordial density fluctuations, using both the cosmic microwave background (cmb) anisotropy and data on galaxies and clusters. Each piece of galaxy and cluster data is…

Astrophysics · Physics 2008-02-03 Andrew R Liddle , David H Lyth

Recent analyses show that $\Lambda$CDM-based models optimised to reproduce the clustering of massive galaxies overestimate their gravitational lensing by about 30\%, the so-called lensing is low problem. Using a state-of-the-art…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Jonas Chaves-Montero , Raul E. Angulo , Sergio Contreras

Motivated by recent developments in inflationary cosmology indicating the possibility of obtaining genuinely open universes in some models, we compare the predictions of cold dark matter (CDM) models in open universes with a variety of…

Astrophysics · Physics 2015-06-24 Andrew R Liddle , David H Lyth , David Roberts , Pedro P T Viana

The initial power spectrum of density perturbations, generated during the inflationary epoch, is now constrained by observations on scales $\lambda>5$~Mpc and has a power-law form. The peculiarities of the inflationary process can lead to…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-04 S. V. Pilipenko , S. A. Drozdov , M. V. Tkachev , A. G. Doroshkevich

A companion paper presents a worked model for evolution through inflation to initial conditions for an isocurvature model for structure formation. It is shown here that the model is consistent with the available observational constraints…

Astrophysics · Physics 2009-10-30 P. J. E. Peebles

Using the apparatus of correlation Gamma-function (``conditional density''), we have analyzed spatial clustering of objects from several different samples of galaxies, clusters and superclusters. On small scales the distribution of objects…

Astrophysics · Physics 2007-05-23 A. V. Tikhonov , D. I. Makarov , A. I. Kopylov

A better understanding of the formation of large-scale structure in the Universe is arguably the most pressing question in cosmology. The most compelling and promising theoretical paradigm, Inflation + Cold Dark Matter, holds that the…

Astrophysics · Physics 2009-10-30 Michael S. Turner

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 investigate the gas mass function of clusters of galaxies to measure the density fluctuation spectrum on cluster scales. The baryon abundance confined in rich clusters is computed from the gas mass function and compared with the mean…

Astrophysics · Physics 2009-10-30 Kazuhiro Shimasaku

The cold dark matter (CDM) model of structure formation, normalized on large scales, leads to excessive pairwise velocity dispersions on small scales. In an attempt to circumvent this problem, we study three scenarios (all with $\Omega=1$)…

High Energy Physics - Phenomenology · Physics 2009-10-22 James. M. Gelb , Ben-Ami Gradwohl , Joshua A. Frieman

The power spectrum of density fluctuations measured from galaxy redshift surveys provides important constraints on models for the formation of large-scale structure. I present new results for a redshift sample of 15,000 galaxies, and review…

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

We discuss the local density fluctuations which arise due to the topological defects that appear after the phase transition of light pseudo-Goldstone bosons. It has been found that in a post-inflationary universe the fluctuations of these…

High Energy Physics - Phenomenology · Physics 2009-10-28 Smaragda Lola

The early reionisation of the Universe inferred from the WMAP polarisation results, if confirmed, poses a problem for the hypothesis that scale-invariant adiabatic density fluctuations account for large-scale structure and galaxy formation.…

Astrophysics · Physics 2009-11-10 Naoshi Sugiyama , Saleem Zaroubi , Joseph Silk

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 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