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Related papers: Non-Gaussian forecasts of weak lensing with and wi…

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Weak lensing maps contain information beyond two-point statistics on small scales. Much recent work has tried to extract this information through a range of different observables or via nonlinear transformations of the lensing field. Here…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Arushi Gupta , José Manuel Zorrilla Matilla , Daniel Hsu , Zoltán Haiman

We present a comparison of Fisher matrix forecasts for cosmological probes with Monte Carlo Markov Chain (MCMC) posterior likelihood estimation methods. We analyse the performance of future Dark Energy Task Force (DETF) stage-III and stage-…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Laura Wolz , Martin Kilbinger , Jochen Weller , Tommaso Giannantonio

We study how well the Gaussian approximation is valid for computing the covariance matrices of the convergence power and bispectrum in weak gravitational lensing analyses. We focus on its impact on the cosmological parameter estimations by…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Masanori Sato , Takahiro Nishimichi

We report the application of implicit likelihood inference to the prediction of the macro-parameters of strong lensing systems with neural networks. This allows us to perform deep learning analysis of lensing systems within a well-defined…

Instrumentation and Methods for Astrophysics · Physics 2023-01-25 Ronan Legin , Yashar Hezaveh , Laurence Perreault-Levasseur , Benjamin Wandelt

We present a framework to compute non-Gaussian likelihoods for two-point correlation functions. The non-Gaussianity is most pronounced on large scales that will be well-measured by stage-IV weak-lensing surveys. We show how such a…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-09 Veronika Oehl , Tilman Tröster

We develop a field-level posterior for cosmological data by marginalizing over initial conditions and noise in a general forward model. While our focus is on large-scale structure data, the results generalize to any weakly non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-29 Massimo Pietroni , Fabian Schmidt

The primary science driver for 3D galaxy surveys is their potential to constrain cosmological parameters. Forecasts of these surveys' effectiveness typically assume Gaussian statistics for the underlying matter density, despite the fact…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-27 Andrew Repp , István Szapudi , Julien Carron , Melody Wolk

Estimators for weak lensing observables such as shear and convergence generally have non-linear corrections, which, in principle, make weak lensing power spectra sensitive to primordial non-Gaussianity. In this paper, we quantitatively…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Donghui Jeong , Fabian Schmidt , Emiliano Sefusatti

Weak lensing convergence can be used directly to map and probe the dark mass distribution in the universe. Building on earlier studies, we recall how the statistics of the convergence field are related to the statistics of the underlying…

Astrophysics · Physics 2009-11-07 Andrew J. Barber , Dipak Munshi , Patrick Valageas

Upcoming galaxy redshift surveys promise to significantly improve current limits on primordial non-Gaussianity (PNG) through measurements of 2- and 3-point correlation functions in Fourier space. However, realizing the full potential of…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-19 Azadeh Moradinezhad Dizgah , Matteo Biagetti , Emiliano Sefusatti , Vincent Desjacques , Jorge Noreña

The Fisher matrix approach (Fisher 1935) allows one to calculate in advance how well a given experiment will be able to estimate model parameters, and has been an invaluable tool in experimental design. In the same spirit, we present here a…

Astrophysics · Physics 2009-01-22 A. F. Heavens , T. D. Kitching , L. Verde

While usually cosmological initial conditions are assumed to be Gaussian, inflationary theories can predict a certain amount of primordial non-Gaussianity which can have an impact on the statistical properties of the lensing observables. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 F. Pace , L. Moscardini , M. Bartelmann , E. Branchini , K. Dolag , M. Grossi , S. Matarrese

We study the information content of summary statistics built from the multi-scale topology of large-scale structures on primordial non-Gaussianity of the local and equilateral type. We use halo catalogs generated from numerical N-body…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-05 Matteo Biagetti , Juan Calles , Lina Castiblanco , Alex Cole , Jorge Noreña

Non-Gaussian likelihoods are essential for modelling complex real-world observations but pose significant computational challenges in learning and inference. Even with Gaussian priors, non-Gaussian likelihoods often lead to analytically…

Machine Learning · Statistics 2024-10-29 Thang D. Bui

We explore the possibility of detecting primordial non-Gaussianity of the local type using weak lensing peak counts. We measure the peak abundance in sets of simulated weak lensing maps corresponding to three models f_NL={0, +100, -100}.…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-19 Laura Marian , Stefan Hilbert , Robert E. Smith , Peter Schneider , Vincent Desjacques

Density-estimation likelihood-free inference (DELFI) has recently been proposed as an efficient method for simulation-based cosmological parameter inference. Compared to the standard likelihood-based Markov Chain Monte Carlo (MCMC)…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-30 Peter L. Taylor , Thomas D. Kitching , Justin Alsing , Benjamin D. Wandelt , Stephen M. Feeney , Jason D. McEwen

In this work, we present Fisher matrix forecast of the tomographic weak lensing power spectrum and bispectrum for three physically distinct types of models of beyond-$\Lambda$CDM: the CPL parametrisation of dynamical dark energy,…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-24 Liantsoa F. Randrianjanahary , Chandrachud B. V. Dash

Fisher Information Matrix methods are commonly used in cosmology to estimate the accuracy that cosmological parameters can be measured with a given experiment, and to optimise the design of experiments. However, the standard approach…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 A. Kiessling , A. N. Taylor , A. F. Heavens

We computed the power spectrum of weak cosmic shear in models with non-Gaussian primordial density fluctuations. Cosmological initial conditions deviating from Gaussianity have recently attracted much attention in the literature, especially…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 C. Fedeli , L. Moscardini

We present exact non-Gaussian joint likelihoods for auto- and cross-correlation functions on arbitrarily masked spherical Gaussian random fields. Our considerations apply to spin-0 as well as spin-2 fields but are demonstrated here for the…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-11 Veronika Oehl , Tilman Tröster