English
Related papers

Related papers: Analysing large scale structure: II. Testing for p…

200 papers

Next-generation galaxy surveys will be able to measure perturbations on scales beyond the equality scale. On these ultra-large scales, primordial non-Gaussianity leaves signatures that can shed light on the mechanism by which perturbations…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-10 Mario Ballardini , William Luke Matthewson , Roy Maartens

Recent second-order perturbation computations have provided an accurate prediction for the primordial gravitational potential $\Phi(x)$ in scenarios in which cosmological perturbations are generated either during or after inflation. This…

Astrophysics · Physics 2008-11-26 M. Liguori , F. K. Hansen , E. Komatsu , S. Matarrese , A. Riotto

With WMAP putting the phenomenological standard model of cosmology on a strong footing, one can look forward to mining the cosmic microwave background (CMB) for fundamental physics with higher sensitivity and on smaller scales. Future CMB…

Astrophysics · Physics 2015-06-24 Manoj Kaplinghat

The cosmic microwave background (CMB) anisotropies are a powerful probe of the early universe, and have largely contributed to establishing the current standard cosmological model. To extract the information encoded in those tiny…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-17 Simon Biquard

We investigate the potential of observations of anisotropies in the cosmic microwave background (CMB) and large-scale structure in the Universe to detect possible modifications of standard inflationary models by physics beyond the Planck…

Astrophysics · Physics 2009-11-10 Oystein Elgaroy , Steen Hannestad

The lensing convergence field describing the weak lensing effect of the Cosmic Microwave Background (CMB) radiation is expected to be subject to mild deviations from Gaussianity. We perform a suite of full-sky lensing simulations using ray…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-18 Jan Hamann , Yuqi Kang

Quantum gravity effects are expected to modify the primordial density fluctuations produced during inflation and leave their imprint on the cosmic microwave background observed today. We present a new analysis discussing whether these…

Astrophysics · Physics 2008-12-18 Nicolaas E. Groeneboom , Oystein Elgaroy

The existence of a cosmic background of primordial gravitational waves (PGWB) is a robust prediction of inflationary cosmology, but it has so far evaded discovery. The most promising avenue of its detection is via measurements of Cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-16 Kai Yi , Yanan Fan , Jan Hamann , Pietro Liò , Yuguang Wang

We study non-Gaussian signatures on the cosmic microwave background (CMB) radiation predicted within inflationary models with non-vacuum initial states for cosmological perturbations. The model incorporates a privileged scale, which implies…

Astrophysics · Physics 2008-11-26 Alejandro Gangui , Jerome Martin , Mairi Sakellariadou

The forthcoming Planck experiment will provide high sensitivity polarization measurements that will allow us to further tighten the f_NL bounds from the temperature data. Monte Carlo simulations of non-Gaussian CMB maps have been used as a…

The cosmic microwave background (CMB) temperature bispectrum is currently the most precise tool for constraining primordial non-Gaussianity (NG). The Planck temperature data tightly constrain the amplitude of local-type NG: $f_{\rm NL}^{\rm…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-06 J. Colin Hill

We present robust constraints on the stochastic gravitational waves (GWs) at Mpc scales from the cosmic microwave background (CMB) data. CMB constraints on GWs are usually characterized as the tensor-to-scalar ratio, assuming specifically a…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-24 Toshiya Namikawa , Shohei Saga , Daisuke Yamauchi , Atsushi Taruya

Minkowski Functionals (MFs) are topological statistics that have become one of many standard tools used for investigating the statistical properties of cosmological random fields. They have found regular use in studies of departures from…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-20 Geraint Pratten , Dipak Munshi

In the first part of this work, I review the theoretical framework of cosmological perturbation theory necessary to understand the generation and evolution of cosmic microwave background (CMB) anisotropies. Using analytical and numerical…

Astrophysics · Physics 2009-09-29 Roberto Trotta

Much recent work on the cosmic microwave background (CMB) has focussed on the angular power spectrum of temperature anisotropies and particularly on the recovery of cosmological parameters from acoustic peaks in the power spectrum. However,…

Astrophysics · Physics 2007-05-23 Marc Kamionkowski

We propose an efficient and model independent method for reconstructing the primordial power spectrum from Cosmic Microwave Background (CMB) and large scale structure observations. The algorithm is based on a Monte Carlo principle and…

Astrophysics · Physics 2009-11-10 Steen Hannestad

In this paper we estimate diffuse foreground minimized Cosmic Microwave Background (CMB) Stokes Q and U polarization maps based upon the fundamental concept of Gaussian nature of CMB and strong non-Gaussian nature of astrophysical polarized…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-10 Ujjal Purkayastha , Rajib Saha

We introduce Koenderink filters as novel tools for statistical cosmology. Amongst several promising applications, they provide a test for the Gaussianity of random fields. We focus on this application and present some preliminary results…

Astrophysics · Physics 2007-05-23 Jens Schmalzing

We introduce a new mathematical tool (a direction-dependent probe) to analyse the randomness of purported isotropic Gaussian random fields on the sphere. We apply the probe to assess the full-sky cosmic microwave background (CMB)…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-29 J. Hamann , Q. T. Le Gia , I. H. Sloan , Y. G. Wang , R. S. Womersley

We use the publicly available code CMBFAST as modified by L. Pogosian and T. Vachaspati to simulate the effects of wiggly cosmic strings on the Cosmic Microwave Background (CMB). Using the modified CMBFAST code which takes into account…

Astrophysics · Physics 2011-05-10 N. Simatos , L. Perivolaropoulos
‹ Prev 1 8 9 10 Next ›