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Applying a transformation to a non-Gaussian field can enhance the information content of the resulting power spectrum, by reducing the correlations between Fourier modes. In the context of weak gravitational lensing, it has been shown that…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-16 Fergus Simpson , Joachim Harnois-Déraps , Catherine Heymans , Raul Jimenez , Benjamin Joachimi , Licia Verde

Precise cosmological inference from next-generation weak lensing surveys requires extracting non-Gaussian information beyond standard two-point statistics. We present a hybrid machine-learning (ML) framework that integrates field-level…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-19 Jiacheng Ding , Chen Su , Ji Yao , Le Zhang , Huanyuan Shan

Photometric surveys produce large-area maps of the galaxy distribution, but with less accurate redshift information than is obtained from spectroscopic methods. Modern photometric redshift (photo-z) algorithms use galaxy magnitudes, or…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 J. Asorey , M. Carrasco Kind , I. Sevilla-Noarbe , R. J. Brunner , J. Thaler

We introduce two kurt-spectra to probe fourth-order statistics of weak lensing convergence maps. Using state-of-the-art numerical simulations, we study the shapes of these kurt-spectra as a function of source redshifts and smoothing angular…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-16 Dipak Munshi , Hayden Lee , Cora Dvorkin , Jason D. McEwen

The capacity of Stage IV lensing surveys to measure the neutrino mass sum and differentiate between the normal and inverted mass hierarchies depends on the impact of nuisance parameters describing small-scale baryonic astrophysics and…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-09 David Copeland , Andy Taylor , Alex Hall

One of the most powerful techniques to study the dark sector of the Universe is weak gravitational lensing. In practice, to infer the reduced shear, weak lensing measures galaxy shapes, which are the consequence of both the intrinsic…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 Sami-Matias Niemi , Thomas Kitching , Mark Cropper

We present results exploring the role that probabilistic deep learning models can play in cosmology from large-scale astronomical surveys through photometric redshift (photo-z) estimation. Photo-z uncertainty estimates are critical for the…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-20 Evan Jones , Tuan Do , Bernie Boscoe , Jack Singal , Yujie Wan , Zooey Nguyen

The available probes of the large scale structure in the Universe have distinct properties: galaxies are a high resolution but biased tracer of mass, while weak lensing avoids such biases but, due to low signal-to-noise ratio, has poor…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-28 Rafal M. Szepietowski , David J. Bacon , Joerg P. Dietrich , Michael Busha , Risa Wechsler , Peter Melchior

We introduce the position-dependent probability distribution function (PDF) of the smoothed matter field as a cosmological observable. In comparison to the PDF itself, the spatial variation of the position-dependent PDF is simpler to model…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-29 Drew Jamieson , Marilena Loverde

A number of alternatives to general relativity exhibit gravitational screening in the non-linear regime of structure formation. We describe a set of algorithms that can produce weak lensing maps of large scale structure in such theories and…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-15 Nicolas Tessore , Hans A. Winther , R. Benton Metcalf , Pedro G. Ferreira , Carlo Giocoli

Weak lensing calculations are often made under the assumption of the Born approximation, where the ray path is approximated as a straight radial line. In addition, lens-lens couplings where there are several deflections along the light ray…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-07 Bjoern Malte Schaefer , Lavinia Heisenberg , Angelos Fotios Kalovidouris , David J. Bacon

We present the gauge-invariant formalism of cosmological weak lensing, accounting for all the relativistic effects due to the scalar, vector, and tensor perturbations at the linear order. While the light propagation is fully described by…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-11 Jaiyul Yoo , Nastassia Grimm , Ermis Mitsou , Adam Amara , Alexandre Refregier

As recently shown by Viola et al., the common (KSB) method for measuring weak gravitational shear creates a non-linear relation between the measured and the true shear of objects. We investigate here what effect such a non-linear…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Matthias Bartelmann , Massimo Viola , Peter Melchior , Björn M. Schäfer

Weak lensing by large-scale structure is a powerful probe of cosmology if the apparent alignments in the shapes of distant galaxies can be accurately measured. Most studies have therefore focused on improving the fidelity of the shape…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-24 Henk Hoekstra , Arun Kannawadi , Thomas D. Kitching

This paper presents a general formalism that allows the derivation of the cumulant generating function and one-point Probability Distribution Function (PDF) of the aperture mass ($\hat{M}_{ap}$), a common observable for cosmic shear…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-31 Paulo Reimberg , Francis Bernardeau

Photometric redshift surveys map the distribution of matter in the Universe through the positions and shapes of galaxies with poorly resolved measurements of their radial coordinates. While a tomographic analysis can be used to recover some…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-06 David Alonso

Weak lensing by large-scale structure is an invaluable cosmological tool given that most of the energy density of the concordance cosmology is invisible. Several large ground-based imaging surveys will attempt to measure this effect over…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-18 Eric M. Huff , Christopher M. Hirata , Rachel Mandelbaum , David Schlegel , Uros Seljak , Robert H. Lupton

Reliable density estimation is fundamental for numerous applications in statistics and machine learning. In many practical scenarios, data are best modeled as mixtures of component densities that capture complex and multimodal patterns.…

Machine Learning · Computer Science 2025-09-30 Mustafa Musab , Joseph K. Chege , Arie Yeredor , Martin Haardt

A small fraction of gravitational-wave (GW) signals from binary black holes (BBHs) will be gravitationally lensed by intervening galaxies and galaxy clusters. Strong lensing will produce multiple identical copies of the GW signal arriving…

General Relativity and Quantum Cosmology · Physics 2026-02-09 Koustav N. Maity , Souvik Jana , Tejaswi Venumadhav , Ankur Barsode , Parameswaran Ajith

We present results of the investigations of the statistical properties of a joint density and velocity divergence probability distribution function (PDF) in the mildly non-linear regime. For that purpose we use both perturbation theory…

Astrophysics · Physics 2009-10-31 F. Bernardeau , M. J. Chodorowski , E. L. Lokas , R. Stompor , A. Kudlicki
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