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Bayesian statistics and Markov Chain Monte Carlo (MCMC) algorithms have found their place in the field of Cosmology. They have become important mathematical and numerical tools, especially in parameter estimation and model comparison. In…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-02 Luis E. Padilla , Luis O. Tellez , Luis A. Escamilla , J. Alberto Vazquez

Cosmic shear is one of the primary probes to test gravity with current and future surveys. There are two main techniques to analyse a cosmic shear survey; a tomographic method, where correlations between the lensing signal in different…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-14 A. Spurio Mancini , R. Reischke , V. Pettorino , B. M. Schäfer , M. Zumalacárregui

Weak gravitational lensing observations probe the spectrum and evolution of density fluctuations and the cosmological parameters which govern them. At low redshifts, the non-linear gravitational evolution of large scale structure produces a…

Astrophysics · Physics 2009-10-31 Asantha Cooray , Wayne Hu

We describe an approximate statistical model for the sample variance distribution of the non-linear matter power spectrum that can be calibrated from limited numbers of simulations. Our model retains the common assumption of a multivariate…

Gravitational lensing of the Cosmic Microwave Background (CMB) encodes cosmological information in the observed anisotropies of temperature and polarization. Accurate extraction of this additional information requires precise modeling of…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-07 Aurélien Benoit-Lévy , Kendrick M. Smith , Wayne Hu

Gaussianizing transformations are used statistically in many non-cosmological fields, but in cosmology, we are only starting to apply them. Here I explain a strategy of analyzing the 1-point function (PDF) of a spatial field, together with…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-22 Mark C. Neyrinck

Persistent homology naturally addresses the multi-scale topological characteristics of the large-scale structure as a distribution of clusters, loops, and voids. We apply this tool to the dark matter halo catalogs from the Quijote…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-31 Jacky H. T. Yip , Matteo Biagetti , Alex Cole , Karthik Viswanathan , Gary Shiu

The line-of-sight peculiar velocities are good indicators of the gravitational fluctuation of the density field. Techniques have been developed to extract cosmological information from the peculiar velocities in order to test the…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-08 Fei Qin

The relationship between the metric and nonrelativistic matter distribution depends on the theory of gravity and additional fields, providing a possible way of distinguishing competing theories. With the assumption that the geometry and…

Astrophysics · Physics 2008-10-28 Mustafa A. Amin , Robert V. Wagoner , Roger D. Blandford

Gravitational lensing has long been used to measure or constrain cosmology models. Although the lensing effect of gravitational waves has not been observed by LIGO/Virgo, it is expected that there can be a few to a few hundreds lensed…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-19 Shaoqi Hou , Xi-Long Fan , Zong-Hong Zhu

We derive constraints on cosmological parameters using the power spectrum of galaxy clustering measured from the final two-degree field galaxy redshift survey (2dFGRS) and a compilation of measurements of the temperature power spectrum and…

Bayesian analysis has become an indispensable tool across many different cosmological fields including the study of gravitational waves, the Cosmic Microwave Background and the 21-cm signal from the Cosmic Dawn among other phenomena. The…

Instrumentation and Methods for Astrophysics · Physics 2023-12-19 Harry T. J. Bevins , William J. Handley , Pablo Lemos , Peter H. Sims , Eloy de Lera Acedo , Anastasia Fialkov , Justin Alsing

We use higher-redshift gamma-ray burst (GRB), HII starburst galaxy (HIIG), and quasar angular size (QSO-AS) measurements to constrain six spatially flat and non-flat cosmological models. These three sets of cosmological constraints are…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-15 Shulei Cao , Joseph Ryan , Narayan Khadka , Bharat Ratra

We consider several well-known f(R) cosmological models and constrain their parameters, namely the deviation parameter b and the cosmological parameters \Omega_m and h. We first obtain analytical approximations for the Hubble rate H(z) and…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-29 Joseph Sultana , Manoj K. Yennapureddy , Fulvio Melia , Demosthenes Kazanas

We show how to efficiently sample the joint posterior of two non-covariant experiments with a large set of nuisance parameters. Specifically, we train an ensemble of normalizing flows to learn the posterior distribution of both experiments.…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-10 Peter L. Taylor , Andrei Cuceu , Chun-Hao To , Erik A. Zaborowski

We apply a new method to measure primordial non-Gaussianity, using the cross-correlation between galaxy surveys and the CMB lensing signal to measure galaxy bias on very large scales, where local-type primordial non-Gaussianity predicts a…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-06 Tommaso Giannantonio , Will J. Percival

Gravitational waves (GWs) from merging compact objects encode direct information about the luminosity distance to the binary. When paired with a redshift measurement, this enables standard-siren cosmology: a Hubble diagram can be…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-26 Amanda M. Farah , Thomas A. Callister , Jose María Ezquiaga , Michael Zevin , Daniel E. Holz

In this letter, we propose an improved cosmological model-independent method to measure cosmic curvature, combining the recent measurements of transverse and line-of-sight directions in the baryon acoustic oscillations (BAO) with cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-09 Xiaolong Gong , Yifei Xu , Tonghua Liu , Shuo Cao , Jianyong Jiang , Yalong Nan , Ruobin Ding

We study the parameter estimation bias induced by intrinsic alignments on a Euclid-like weak lensing survey. For the intrinsic alignment signal we assume a composite alignment model for elliptical and spiral galaxies using tidal shearing…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-15 Robert Reischke , Björn Malte Schäfer

Since gravitational lensing effects directly probe inhomogeneities of dark matter, lensing-galaxy cross-correlations can provide us important information on the relation between dark matter and galaxy distributions, i.e., the bias. In this…

Astrophysics · Physics 2009-11-10 Z. H. Fan
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