English
Related papers

Related papers: Three-dimensional shapelets and an automated class…

200 papers

We present a detailed description and validation of our massively-parallel update to the mass-Peak Patch method, a fully predictive initial-space algorithm to quickly generate dark matter halo catalogues in very large cosmological volumes.…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-05 George Stein , Marcelo A. Alvarez , J. Richard Bond

We train a machine learning algorithm to learn cosmological structure formation from N-body simulations. The algorithm infers the relationship between the initial conditions and the final dark matter haloes, without the need to introduce…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-02 Luisa Lucie-Smith , Hiranya V. Peiris , Andrew Pontzen , Michelle Lochner

We use numerical simulations of critically-closed cold dark matter (CDM) models to study the effects of numerical resolution on observable quantities. We study simulations with up to $256^3$ particles using the particle-mesh (PM) method and…

Astrophysics · Physics 2009-10-22 James M. Gelb , Edmund Bertschinger

Both humans and deep learning models can recognize objects from 3D shapes depicted with sparse visual information, such as a set of points randomly sampled from the surfaces of 3D objects (termed a point cloud). Although deep learning…

Computer Vision and Pattern Recognition · Computer Science 2025-07-15 Shuhao Fu , Philip J. Kellman , Hongjing Lu

While the use of galaxy clusters as {\it tools} to probe cosmology is established, their conventional description still relies on the spherical and/or isothermal models that were proposed more than 20 years ago. We present, instead, a…

Astrophysics · Physics 2009-11-07 Jounghun Lee , Yasushi Suto

We investigate the possibility of applying machine learning techniques to images of strongly lensed galaxies to detect a low mass cut-off in the spectrum of dark matter sub-halos within the lens system. We generate lensed images of systems…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-13 Sreedevi Varma , Malcolm Fairbairn , Julio Figueroa

Halo Models of large scale structure provide powerful and indispensable tools for phenomenological understanding of the clustering of matter in the Universe. While the halo model builds structures out of the superposition of haloes,…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-26 Alice Chen , Niayesh Afshordi

Predicting the spatial distribution of objects as a function of cosmology is an essential ingredient for the exploitation of future galaxy surveys. In this paper we show that a specially-designed suite of gravity-only simulations together…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-28 S. Contreras , R. E. Angulo , M. Zennaro , G. Aricó , M. Pellejero-Ibañez

AI super-resolution, combining deep learning and N-body simulations has been shown to successfully reproduce the large scale structure and halo abundances in the Lambda Cold Dark Matter cosmological model. Here, we extend its use to models…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-16 Meris Sipp , Patrick LaChance , Rupert Croft , Yueying Ni , Tiziana Di Matteo

We present a new high-resolution N-body algorithm for cosmological simulations. The algorithm employs a traditional particle-mesh technique on a cubic grid and successive multilevel relaxations on the finer meshes, introduced recursively in…

Astrophysics · Physics 2009-10-30 Andrey V. Kravtsov , Anatoly A. Klypin , Alexei M. Khokhlov

We use explainable neural networks to connect the evolutionary history of dark matter halos with their density profiles. The network captures independent factors of variation in the density profiles within a low-dimensional representation,…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-22 Luisa Lucie-Smith , Hiranya V. Peiris , Andrew Pontzen

Dark matter density is formally infinite at the location of caustic surfaces, where dark matter sheet folds in phase space. The caustics separate multi-stream regions with different number of streams. Volume elements change the parity by…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-03 Segei F. Shandarin

We present a statistical model for $3$D human faces in varying expression, which decomposes the surface of the face using a wavelet transform, and learns many localized, decorrelated multilinear models on the resulting coefficients. Using…

Computer Vision and Pattern Recognition · Computer Science 2014-07-02 Alan Brunton , Timo Bolkart , Stefanie Wuhrer

In the area of 3D shape analysis, the geometric properties of a shape have long been studied. Instead of directly extracting representative features using expert-designed descriptors or end-to-end deep neural networks, this paper is…

Computer Vision and Pattern Recognition · Computer Science 2021-12-22 Zongji Wang , Yunfei Liu , Feng Lu

This paper uses clustering algorithms to introduce a shape framework for deformable objects. Until now, the shape detection of the deformable objects has faced several challenges: 1) unable to form a unified framework for multiple shapes;…

Robotics · Computer Science 2023-12-19 Fangqing Chen

Galaxy clusters trace the most massive dark matter haloes, whose shapes and orientations reflect the imprint of the cosmic large-scale tidal field. This paper introduces the Subhalo-based Halo Alignment and Projected Ellipticity (SHAPE)…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-06 Shogo Ishikawa , Atsushi Taruya , Takahiro Nishimichi , Teppei Okumura , Satoshi Tanaka

We investigate the collapse and internal structure of dark matter halos. We consider halo formation from initially scale-free perturbations, for which gravitational collapse is self-similar. Fillmore and Goldreich (1984) and Bertschinger…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-21 Yoram Lithwick , Neal Dalal

We provide a set of general tools for studying the alignments of dark matter halos and galaxies with respect to the large scale structure. The statistics of the positioning of these objects is represented by a Probability Distribution…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-08 Juan E. Betancort-Rijo , Ignacio Trujillo

Accurately predicting structural properties of dark matter halos is one of the fundamental goals of modern cosmology. We use the new suite of MultiDark cosmological simulations to study the evolution of dark matter halo density profiles,…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 Anatoly Klypin , Gustavo Yepes , Stefan Gottlober , Francisco Prada , Steffen Hess

This work investigates a set of cosmological collisionless N-body simulations with featured power spectra of initial perturbations in the context of the core-cusp and satellites problems. On the studied power spectra some scales of…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-14 Vadim Semenov , Sergey Pilipenko , Andrei Doroshkevich , Vladimir Lukash , Elena Mikheeva