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Related papers: Field-Based Physical Inference From Peculiar Veloc…

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We study the cosmic peculiar velocity field as traced by a sample of 1184 spiral, elliptical and S0 galaxies, grouped in 704 objects. We carry out a statistical analysis, by calculating bulk flows and velocity correlation functions for this…

Astrophysics · Physics 2007-05-23 F. Lucchin , S. Matarrese , L. Moscardini , G. Tormen

The aim of this paper is to establish a nonlinear variational approach to the reconstruction of moving density images from indirect dynamic measurements. Our approach is to model the dynamics as a hyperelastic deformation of an initial…

Numerical Analysis · Mathematics 2015-12-01 Martin Burger , Jan Modersitzki , Sebastian Suhr

The peculiar velocities of dark matter halos are crucial to study many issues in cosmology and galaxy evolution. In this study, by using the state-of-the-art deep learning technique, a UNet-based neural network, we propose to reconstruct…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-10 Ziyong Wu , Liang Xiao , Xu Xiao , Jie Wang , Xi Kang , Yang Wang , Xin Wang , Le Zhang , Xiao-Dong Li

The inverse problem which consists of determining the flow at the Earth's Core Mantle Boundary according to an outer core magnetic field and secular variation model, has been investigated through a Bayesian formalism. To circumvent the…

Geophysics · Physics 2015-06-17 Julien Baerenzung , Matthias Holschneider , Vincent Lesur

We explore the observational prospects for detecting gravitational lensing induced by cosmological matter currents, a relativistic correction to the standard density lensing effect arising from the motion of matter. We propose to isolate…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-25 C. Murray , R. Kou , J. G. Bartlett

This paper presents a hierarchical Bayesian model to reconstruct sparse images when the observations are obtained from linear transformations and corrupted by an additive white Gaussian noise. Our hierarchical Bayes model is well suited to…

Data Analysis, Statistics and Probability · Physics 2011-01-19 Nicolas Dobigeon , Alfred O. Hero , Jean-Yves Tourneret

We study the inverse problem of reconstructing an incompressible velocity field $\boldsymbol{v}$ from observations of the induced magnetic field $\boldsymbol{b}$. In the presence of a strong, constant background field $\mathbf{F}$, the…

Analysis of PDEs · Mathematics 2026-02-26 Yacine Mokhtari , Christina Frederick , Yunan Yang , Bjorn Engquist

In cosmology it has become usual to introduce new entities as dark matter and dark energy in order to explain otherwise unexplained observational facts. Here, we propose a different approach treating spacetime as a continuum endowed with…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. Tartaglia , M. Capone

While learning the maximum likelihood value of parameters of an undirected graphical model is hard, modelling the posterior distribution over parameters given data is harder. Yet, undirected models are ubiquitous in computer vision and text…

Machine Learning · Computer Science 2012-07-02 Max Welling , Sridevi Parise

The ability to obtain reliable point estimates of model parameters is of crucial importance in many fields of physics. This is often a difficult task given that the observed data can have a very high number of dimensions. In order to…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-15 Janis Fluri , Aurelien Lucchi , Tomasz Kacprzak , Alexandre Refregier , Thomas Hofmann

We present the data-driven reconstruction of gravitational theories and Dark Energy models on cosmological scales. We showcase the power of present cosmological probes at constraining these models and quantify the knowledge of their…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-22 Marco Raveri

The initial shear field, characterized by a primordial perturbation potential, plays a crucial role in the formation of large scale structures. Hence, considerable analytic work has been based on the joint distribution of its eigenvalues,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Graziano Rossi

We develop a hybrid GNN-CNN architecture for the reconstruction of 3-dimensional continuous cosmological matter fields from discrete point clouds, provided by observed galaxy catalogs. Using the CAMELS hydrodynamical cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-06 Yurii Kvasiuk , Jordan Krywonos , Matthew C. Johnson , Moritz Münchmeyer

We show that a regression of unsmoothed peculiar velocity measurements against peculiar velocities predicted from a smoothed galaxy density field leads to a biased estimate of the cosmological density parameter Omega, even when galaxies…

Astrophysics · Physics 2009-10-31 Andreas A. Berlind , Vijay K. Narayanan , David H. Weinberg , .

We present BAM: a novel Bias Assignment Method envisaged to generate mock catalogs. Combining the statistics of dark matter tracers from a high resolution cosmological $N$-body simulation and the dark matter density field calculated from…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-21 A. Balaguera-Antolínez , Francisco-Shu Kitaura , Marcos Pellerejo-Ibañez , Cheng Zhao , Tom Abel

This is a somewhat extended version of the original July 93 report. It is proved that the cosmological density perturbation is associated with a peculiar velocity field. This allows a simple formulation of cosmological perturbation theory,…

Astrophysics · Physics 2010-11-01 Marco Bruni , David H. Lyth

The local Universe provides a unique opportunity for testing cosmology and theories of structure formation. To facilitate this opportunity we present a new method for the reconstruction of the quasi-linear matter density and velocity fields…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-11 Yehuda Hoffman , Edoardo Carlesi , Daniel Pomarède , Hélène M. Courtois , Stefan Gottlöber , Noam I. Libeskind , Jenny G. Sorce , Gustavo Yepes

We present a novel method to search for structures of coherently aligned patterns in ultra-high energy cosmic-ray arrival directions simultaneously across the entire sky. This method can be used to obtain information on the Galactic…

Instrumentation and Methods for Astrophysics · Physics 2022-01-31 Marcus Wirtz , Teresa Bister , Martin Erdmann

Proton imaging is a powerful technique for imaging electromagnetic fields within an experimental volume, in which spatial variations in proton fluence are a result of deflections to proton trajectories due to interaction with the fields.…

Data Analysis, Statistics and Probability · Physics 2021-09-10 Joseph M. Levesque , Lauren J. Beesley

We use cosmological N-body simulations to investigate whether measurements of the moments of large-scale structure can yield constraints on primordial non-Gaussianity. We measure the variance, skewness, and kurtosis of the evolved density…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-24 Qingqing Mao , Andreas A. Berlind , Cameron K. McBride , Robert J. Scherrer , Roman Scoccimarro , Marc Manera