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Related papers: Bayesian Cosmic Void Finding with Graph Flows

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We present a new method to find voids in cosmological simulations based on the tidal and the velocity shear tensors definitions of the cosmic web. We use the fractional anisotropy (FA) computed from the eigenvalues of each web scheme as a…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-26 Sebastian Bustamante , Jaime E. Forero-Romero

As the volume and quality of modern galaxy surveys increase, so does the difficulty of measuring the cosmological signal imprinted in galaxy shapes. Weak gravitational lensing sourced by the most massive structures in the Universe generates…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-04 Benjamin Remy , Francois Lanusse , Jean-Luc Starck

We present a simple empirical function for the average density profile of cosmic voids, identified via the watershed technique in $\Lambda$CDM N-body simulations. This function is universal across void size and redshift, accurately…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-09 Nico Hamaus , P. M. Sutter , Benjamin D. Wandelt

Cosmic voids constitute promising cosmological laboratories. However, a full description of all the redshift-space effects that affect observational measurements is mandatory in order to obtain unbiased cosmological constraints. We make a…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-30 Carlos M. Correa , Dante J. Paz

Weak lensing mass-mapping is a useful tool to access the full distribution of dark matter on the sky, but because of intrinsic galaxy ellipticies and finite fields/missing data, the recovery of dark matter maps constitutes a challenging…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-05 Benjamin Remy , Francois Lanusse , Niall Jeffrey , Jia Liu , Jean-Luc Starck , Ken Osato , Tim Schrabback

We introduce a simple model for the formation of voids. In this model the underdensity of galaxies in voids is the product of two factors. The first arises from a gravitational expansion of the negative density perturbation. The second is…

Astrophysics · Physics 2009-10-31 Yasmin Friedmann , Tsvi Piran

Recent advances in graph convolutional networks have significantly improved the performance of chemical predictions, raising a new research question: "how do we explain the predictions of graph convolutional networks?" A possible approach…

Machine Learning · Computer Science 2018-07-06 Hirotaka Akita , Kosuke Nakago , Tomoki Komatsu , Yohei Sugawara , Shin-ichi Maeda , Yukino Baba , Hisashi Kashima

Cosmology inference of galaxy clustering at the field level with the EFT likelihood in principle allows for extracting all non-Gaussian information from quasi-linear scales, while robustly marginalizing over any astrophysical uncertainties.…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-31 Julia Stadler , Fabian Schmidt , Martin Reinecke

In this paper we introduce a reliable, fully automated and fast algorithm to detect extended extragalactic radio sources (cluster of galaxies, filaments) in existing and forthcoming surveys (like LOFAR and SKA). The proposed solution is…

Instrumentation and Methods for Astrophysics · Physics 2018-09-11 Claudio Gheller , Franco Vazza , Annalisa Bonafede

Matrix completion and robust principal component analysis have been widely used for the recovery of data suffering from missing entries or outliers. In many real-world applications however, the data is also time-varying, and the naive…

Signal Processing · Electrical Eng. & Systems 2019-06-25 Charul , Uttkarsha Bhatt , Pravesh Biyani , Ketan Rajawat

We describe a new method of overcoming problems inherent in peculiar velocity surveys by using data compression as a filter with which to separate large-scale, linear flows from small-scale noise that biases the results systematically. We…

Astrophysics · Physics 2007-05-23 Hume A Feldman , Richard Watkins , Adrian Melott , Will Chambers

We present results exploring the role that probabilistic deep learning models can play in cosmology from large scale astronomical surveys through estimating the distances to galaxies (redshifts) from photometry. Due to the massive scale of…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-16 Evan Jones , Tuan Do , Bernie Boscoe , Yujie Wan , Zooey Nguyen , Jack Singal

Cosmologists at the Institute of Computational Cosmology, Durham University, have developed a state of the art model of galaxy formation known as Galform, intended to contribute to our understanding of the formation, growth and subsequent…

Methodology · Statistics 2014-05-21 Ian Vernon , Michael Goldstein , Richard Bower

We present a proof-of-concept of a novel and fully Bayesian methodology designed to detect halos of different masses in cosmological observations subject to noise and systematic uncertainties. Our methodology combines the previously…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Alexander I. Merson , Jens Jasche , Filipe B. Abdalla , Ofer Lahav , Benjamin Wandelt , D. Heath Jones , Matthew Colless

Voids represent a unique environment for the study of galaxy evolution, as the lower density environment is expected to result in shorter merger histories and slower evolution of galaxies. This provides an ideal opportunity to test theories…

We present predictions for numerous statistics related to the presence of voids in the distribution of galaxies in a cold dark matter model of structure formation using a semi-analytic model of galaxy formation. Our study is able to probe…

Astrophysics · Physics 2009-11-07 A. J. Benson , Fiona Hoyle , Fernando Torres , Michael S. Vogeley

Weak gravitational lensing is a powerful probe of the large-scale cosmic matter distribution. Wide-field galaxy surveys allow us to generate the so-called weak lensing maps, but actual observations suffer from noise due to imperfect…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-21 Masato Shirasaki , Naoki Yoshida , Shiro Ikeda

We study a family of parametric statistical models based on gamma distributions, which do give realistic descriptions for other stochastic porous media. Gamma distributions contain as a special case the exponential distributions, which…

Astrophysics · Physics 2016-08-30 C. T. J. Dodson

We present a Bayesian reconstruction method which maps a galaxy distribution from redshift-space to real-space inferring the distances of the individual galaxies. The method is based on sampling density fields assuming a lognormal prior…

Bayesian (Probabilistic) Machine Learning is used to probe the opacity of the Universe. It relies on a generative process where the model is the key object to generate the data involving the unknown parameters of the model, our prior…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-17 Emilio Elizalde , Martiros Khurshudyan