English
Related papers

Related papers: Errors on errors - Estimating cosmological paramet…

200 papers

General relativistic corrections to the galaxy power spectrum appearing at the horizon scale, if neglected, may induce biases on the measured values of the cosmological parameters. In this paper, we study the impact of general relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 L. Lopez-Honorez , O. Mena , S. Rigolin

Upcoming surveys will map the growth of large-scale structure with unprecented precision, improving our understanding of the dark sector of the Universe. Unfortunately, much of the cosmological information is encoded by the small scales,…

We discuss the problems of applying Maximum Likelihood methods to the CMB and how one can make it both efficient and optimal. The solution is a generalised eigenvalue problem that allows virtually no loss of information about the parameter…

Astrophysics · Physics 2007-05-23 Andy Taylor , Alan Heavens , Bill Ballinger , Max Tegmark

In the context of the averaging problem in relativistic cosmology, we provide a key to the interpretation of cosmological parameters by taking into account the actual inhomogeneous geometry of the Universe. We discuss the relation between…

General Relativity and Quantum Cosmology · Physics 2009-07-10 Thomas Buchert , Mauro Carfora

We forecast the future constraints on scale-dependent parametrizations of galaxy bias and their impact on the estimate of cosmological parameters from the power spectrum of galaxies measured in a spectroscopic redshift survey. For the…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-18 L. Amendola , E. Menegoni , C. Di Porto , M. Corsi , E. Branchini

Astrophysics and cosmology can be used to test the standard model of particle physics under conditions and over distance and time scales not accessible to laboratory experiments. Most of the astrophysical observations are in good agreement…

High Energy Physics - Phenomenology · Physics 2016-09-01 Arnon Dar

Forthcoming cosmic shear surveys will make precise measurements of the matter density field down to very small scales, scales which are dominated by baryon feedback. The modelling of baryon feedback is crucial to ensure unbiased…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-10 Alessandro Maraio , Alex Hall , Andy Taylor

The general idea of determining cosmological parameters with gravitational lensing statistics is outlined, and then recent work---with an emphasis on applicability to all cosmological models, observational bias, better statistics and…

Astrophysics · Physics 2011-04-15 Phillip Helbig

An accurate covariance matrix is essential for obtaining reliable cosmological results when using a Gaussian likelihood. In this paper we study the covariance of pseudo-$C_\ell$ estimates of tomographic cosmic shear power spectra. Using two…

One of the primary sources of uncertainties in modeling the cosmic-shear power spectrum on small scales is the effect of baryonic physics. Accurate cosmology for Stage-IV surveys requires knowledge of the matter power spectrum deep in the…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-15 Maria G. Moreira , Felipe Andrade-Oliveira , Xiao Fang , Hung-Jin Huang , Elisabeth Krause , Vivian Miranda , Rogerio Rosenfeld , Marko Simonović

We study how well perturbative forward modeling can constrain cosmological parameters compared to conventional analyses. We exploit the fact that in perturbation theory the field-level posterior can be computed analytically in the limit of…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-31 Giovanni Cabass , Marko Simonović , Matias Zaldarriaga

Cosmological covariance matrices are fundamental for parameter inference, since they are responsible for propagating uncertainties from the data down to the model parameters. However, when data vectors are large, in order to estimate…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-13 Natalí S. M. de Santi , L. Raul Abramo

Weak lensing of galaxies by large scale structure can potentially measure cosmological quantities as accurately as the cosmic microwave background (CMB). However, the relation between observables and fundamental parameters is more complex…

Astrophysics · Physics 2009-10-31 Wayne Hu , Max Tegmark

The normal parameters are a non--linear transformation of the cosmological parameters whose likelihood function is very well--approximated by a normal distribution. This transformation serves as an extreme form of data compression allowing…

Astrophysics · Physics 2009-11-07 Mike Chu , Manoj Kaplinghat , Lloyd Knox

We revisit the issue of cosmological parameter estimation in light of current and upcoming high-precision measurements of the cosmic microwave background power spectrum. Physical quantities which determine the power spectrum are reviewed,…

Astrophysics · Physics 2009-11-07 Arthur Kosowsky , Milos Milosavljevic , Raul Jimenez

Computing the inverse covariance matrix (or precision matrix) of large data vectors is crucial in weak lensing (and multi-probe) analyses of the large scale structure of the universe. Analytically computed covariances are noise-free and…

Instrumentation and Methods for Astrophysics · Physics 2017-12-06 Oliver Friedrich , Tim Eifler

Cosmological weak lensing by the large scale structure of the Universe, cosmic shear, is coming of age as a powerful probe of the parameters describing the cosmological model and matter power spectrum. It complements CMB studies, by…

Astrophysics · Physics 2009-11-10 Patrick Simon , Lindsay J. King , Peter Schneider

Obtaining the set of cosmological parameters consistent with observational data is an important exercise in current cosmological research. It involves finding the global maximum of the likelihood function in the multi-dimensional parameter…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-03 Jayanti Prasad , Tarun Souradeep

Future galaxy surveys will provide accurate measurements of the matter power spectrum across an unprecedented range of scales and redshifts. The analysis of these data will require one to accurately model the imprint of non-linearities of…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-11 Linda Blot , Pier-Stefano Corasaniti , Yann Rasera , Shankar Agarwal

Over the next decade, improvements in cosmological parameter constraints will be driven by surveys of large-scale structure. Its inherent non-linearity suggests that significant information will be embedded in higher correlations beyond the…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Joyce Byun , Alexander Eggemeier , Donough Regan , David Seery , Robert E. Smith