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Current and upcoming cosmological surveys will produce unprecedented amounts of high-dimensional data, which require complex high-fidelity forward simulations to accurately model both physical processes and systematic effects which describe…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-11 Aizhan Akhmetzhanova , Carolina Cuesta-Lazaro , Siddharth Mishra-Sharma

Due to the complexity of the traffic flow dynamics in urban road networks, most quantitative descriptions of city traffic so far are based on computer simulations. This contribution pursues a macroscopic (fluid-dynamic) simulation approach,…

Fluid Dynamics · Physics 2015-03-18 Amin Mazloumian , Nikolas Geroliminis , Dirk Helbing

We present a data-driven method for reconstructing the galactic acceleration field from phase-space measurements of stellar streams. Our approach is based on a flexible and differentiable fit to the stream in phase-space, enabling a direct…

Astrophysics of Galaxies · Physics 2023-03-31 Jacob Nibauer , Vasily Belokurov , Miles Cranmer , Jeremy Goodman , Shirley Ho

Flows in networks (or graphs) play a significant role in numerous computer vision tasks. The scalar-valued edges in these graphs often lead to a loss of information and thereby to limitations in terms of expressiveness. For example,…

Computer Vision and Pattern Recognition · Computer Science 2023-05-16 Viktoria Ehm , Daniel Cremers , Florian Bernard

As an alternative way of describing the cosmological velocity field, we discuss the evolution of rotational invariants constructed from the velocity gradient tensor. Compared with the traditional divergence-vorticity decomposition, these…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-16 Xin Wang , Alex Szalay , Miguel A. Aragon-Calvo , Mark C. Neyrinck , Gregory L. Eyink

The cosmic web consists of a nested hierarchy of structures: voids, walls, filaments, and clusters. These structures interconnect and can encompass one another, collectively shaping an intricate network. Here we introduce the Hierarchical…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-31 M. A. Aragon-Calvo

The viscosity of lipid bilayer membranes plays an important role in determining the diffusion constant of embedded proteins and the dynamics of membrane deformations, yet it has historically proven very difficult to measure. Here we…

Soft Condensed Matter · Physics 2013-08-30 Aurelia R. Honerkamp-Smith , Francis G. Woodhouse , Vasily Kantsler , Raymond E. Goldstein

Cosmological field-level inference requires differentiable forward models that solve the challenging dynamics of gas and dark matter under hydrodynamics and gravity. We propose a hybrid approach where gravitational forces are computed using…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-31 Arne Thomsen , Tilman Tröster , François Lanusse

Cosmological N-body simulations are crucial for understanding how the Universe evolves. Studying large-scale distributions of matter in these simulations and comparing them to observations usually involves detecting dense clusters of…

Astrophysics of Galaxies · Physics 2019-12-25 Aidan Reilly , Nikita Ivkin , Gerard Lemson , Vladimir Braverman , Alexander Szalay

We present a new approach for the identification of ultra-high energy cosmic rays from sources using dynamic graph convolutional neural networks. These networks are designed to handle sparsely arranged objects and to exploit their short-…

High Energy Astrophysical Phenomena · Physics 2020-12-09 Teresa Bister , Martin Erdmann , Jonas Glombitza , Niklas Langner , Josina Schulte , Marcus Wirtz

Recent application of the Bayesian algorithm BORG to the Sloan Digital Sky Survey (SDSS) main sample galaxies resulted in the physical inference of the formation history of the observed large-scale structure from its origin to the present…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Florent Leclercq , Jens Jasche , Benjamin Wandelt

The cosmic web structure is studied with the concepts and methods of fractal geometry, employing the adhesion model of cosmological dynamics as a basic reference. The structures of matter clusters and cosmic voids in cosmological N-body…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-06 Jose Gaite

Using limited observations of the velocity field of the two-dimensional Navier-Stokes equations, we successfully reconstruct the steady body force that drives the flow. The number of observed data points is less than 10\% of the number of…

Fluid Dynamics · Physics 2024-02-26 Aseel Farhat , Adam Larios , Vincent R. Martinez , Jared P. Whitehead

The motion of an interface separating two fluids under the effect of electric fields is a subject that has picked the attention of researchers from different areas. While there is an abundance of studies investigating the free surface wave…

Fluid Dynamics · Physics 2023-03-29 Marcelo V. Flamarion , Tao Gao , Roberto Ribeiro-Jr

Numerical and experimental turbulence simulations are nowadays reaching the size of the so-called big data, thus requiring refined investigative tools for appropriate statistical analyses and data mining. We present a new approach based on…

Fluid Dynamics · Physics 2017-01-05 Stefania Scarsoglio , Giovanni Iacobello , Luca Ridolfi

In this work, the nonlinear dynamics of a fully three-dimensional multicomponent vesicle in shear flow are explored. Using a volume- and area-conserving projection method coupled to a gradient-augmented level set and surface phase method,…

Soft Condensed Matter · Physics 2018-05-22 Prerna Gera , David Salac

We study the fully nonlinear, nonlocal dynamics of two-dimensional multicomponent vesicles in a shear flow with matched viscosity of the inner and outer fluids. Using a nonstiff, pseudo-spectral boundary integral method, we investigate…

Soft Condensed Matter · Physics 2016-11-01 Kai Liu , Gary R. Marple , Shuwang Li , Shravan Veerapaneni , John Lowengrub

Data-stream clustering is an ever-expanding subdomain of knowledge extraction. Most of the past and present research effort aims at efficient scaling up for the huge data repositories. Our approach focuses on qualitative improvement, mainly…

Artificial Intelligence · Computer Science 2008-11-05 Alain Lelu , Pascal Cuxac , Joel Johansson

A three-dimensional (3D) scanning velocimetry system is developed to quantify the 3D configurations of particles and their surrounding volumetric, three-component velocity fields. The approach uses a translating laser sheet to rapidly scan…

Fluid Dynamics · Physics 2021-08-04 Matt K. Fu , Isabel A. Houghton , John O. Dabiri

We study the cosmological information contained in the cosmic web, categorized as four structure types: nodes, filaments, walls, and voids, using the Quijote simulations and a modified nexus+ algorithm. We show that splitting the density…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-15 James Sunseri , Adrian E. Bayer , Jia Liu