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Related papers: Large-scale structures in the $\Lambda$CDM Univers…

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The large-scale structure of the Universe is characterised by a web-like structure made of voids, sheets, filaments, and knots. The structure of this so-called cosmic web is dictated by the local velocity shear tensor. In particular, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 E. Tempel , N. I. Libeskind , Y. Hoffman , L. J. Liivamägi , A. Tamm

We demonstrate the potential of Deep Learning methods for measurements of cosmological parameters from density fields, focusing on the extraction of non-Gaussian information. We consider weak lensing mass maps as our dataset. We aim for our…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Jorit Schmelzle , Aurelien Lucchi , Tomasz Kacprzak , Adam Amara , Raphael Sgier , Alexandre Réfrégier , Thomas Hofmann

The models of the Internet reported in the literature are mainly aimed at reproducing the scale-free structure, the high clustering coefficient and the small world effects found in the real Internet, while other important properties (e.g.…

Physics and Society · Physics 2011-11-10 F. A. Rodrigues , P. R. Villas Boas , G. Travieso , L. da F. Costa

Testing the standard cosmological model ($\Lambda$CDM) at small scales is challenging. Galaxies that inhabit low-mass dark matter halos provide an ideal test bed for dark matter models by linking observational properties of galaxies at…

Astrophysics of Galaxies · Physics 2023-06-14 Amy Sardone , Annika H. G. Peter , Alyson M. Brooks , Jane Kaczmarek

We construct a viable cosmological model based on velocity diffusion of matter particles. In order to ensure the conservation of the total energy-momentum tensor in the presence of diffusion, we include a cosmological scalar field $\phi$…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-04 Simone Calogero , Hermano Velten

We present a numerical study of dark matter halo concentrations in $\Lambda$CDM and self-similar cosmologies. We show that the relation between concentration, $c$, and peak height, $\nu$, exhibits the smallest deviations from universality…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-21 Benedikt Diemer , Andrey V. Kravtsov

Galaxies are theorized to form and co-evolve with their dark matter halos, such that their stellar masses and halo masses should be well-correlated. However, it is not known whether other observable galaxy features, such as their…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-19 Austin J. Larson , John F. Wu , Craig Jones

The circum-galactic medium (CGM) can feasibly be mapped by multiwavelength surveys covering broad swaths of the sky. With multiple large datasets becoming available in the near future, we develop a likelihood-free Deep Learning technique…

We train deep learning models on thousands of galaxy catalogues from the state-of-the-art hydrodynamic simulations of the CAMELS project to perform regression and inference. We employ Graph Neural Networks (GNNs), architectures designed to…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-10 Pablo Villanueva-Domingo , Francisco Villaescusa-Navarro

We present a pipeline for characterizing and constraining initial conditions in cosmology via persistent homology. The cosmological observable of interest is the cosmic web of large scale structure, and the initial conditions in question…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-08 Alex Cole , Matteo Biagetti , Gary Shiu

The paradigm of \Lambda CDM cosmology works impressively well and with the concept of inflation it explains the universe after the time of decoupling. However there are still a few concerns; after much effort there is no detection of dark…

General Physics · Physics 2017-03-22 B. Vlahovic

Complex networks describe a wide range of systems in nature and society, much quoted examples including the cell, a network of chemicals linked by chemical reactions, or the Internet, a network of routers and computers connected by physical…

Statistical Mechanics · Physics 2016-08-31 Reka Albert , Albert-Laszlo Barabasi

We review the main tools which allow for the statistical characterization of weighted networks. We then present two case studies, the airline connection network and the scientific collaboration network, which are representative of critical…

Statistical Mechanics · Physics 2009-11-10 Marc Barthelemy , Alain Barrat , Romualdo Pastor-Satorras , Alessandro Vespignani

We use a 64$h^{-1}$Mpc dark matter (DM) only cosmological simulation to examine the large scale orientation of haloes and substructures with respect the cosmic web. A web classification scheme based on the velocity shear tensor is used to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Noam I. Libeskind , Yehuda Hoffman , Alexander Knebe , Matthias Steinmetz , Stefan Gottlöber , Ofer Metuki , Gustavo Yepes

Numerical simulations play a key important role in modern cosmology. Examples are plenty including the cosmic web - large scale structure of the distribution of galaxies in space - which was first observed in N-body simulations and later…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-07 Anatoly Klypin , Francisco Prada , Johan Comparat

High resolution N-body simulations show that the density profiles of dark matter halos formed in the standard CDM cosmogony can be fit accurately by scaling a simple ``universal'' profile. Regardless of their mass, halos are nearly…

Astrophysics · Physics 2007-05-23 Julio F. Navarro

Warm Dark Matter (WDM) cosmologies are a viable alternative to the Cold Dark Matter (CDM) scenario. Unfortunately, an accurate scrutiny of the WDM predictions with N-body simulations has proven difficult due to numerical artefacts. Here, we…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Raul E. Angulo , Oliver Hahn , Tom Abel

We have developed a machine learning algorithm capable of detecting ``out-of-domain data'' for trustworthy cosmological inference. By using data from two separate suites of cosmological simulations, we show that our algorithm is able to…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-21 Ethan Tregidga , David Harvey , Luca Biggio , Felix Vecchi

We compare the structure and kinematics of the 11 known satellites of the Milky Way with high resolution simulations of the formation of its dark halo in a LambdaCDM universe. In contrast to earlier work, we find excellent agreement. The…

Astrophysics · Physics 2009-11-07 Felix Stoehr , Simon D. M. White , Giuseppe Tormen , Volker Springel

We present a novel halo painting network that learns to map approximate 3D dark matter fields to realistic halo distributions. This map is provided via a physically motivated network with which we can learn the non-trivial local relation…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-14 Doogesh Kodi Ramanah , Tom Charnock , Guilhem Lavaux