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Related papers: Doing numerical cosmology with the Cactus code

200 papers

High performance computing numerical simulations are today one of the more effective instruments to implement and study new theoretical models, and they are mandatory during the preparatory phase and operational phase of any scientific…

Instrumentation and Methods for Astrophysics · Physics 2019-04-29 Giuliano Taffoni , Giuseppe Murante , Luca Tornatore , David Goz , Stefano Borgani , Manolis Katevenis , Nikolaos Chrysos , Manolis Marazakis

We initiate a formal study of logical inferences in context of the measure problem in cosmology or what we call cosmic logic. We describe a simple computational model of cosmic logic suitable for analysis of, for example, discretized…

High Energy Physics - Theory · Physics 2019-01-15 Vitaly Vanchurin

A cosmological model describing the evolution of n Ricci-flat spaces (n>1) in the presence of 1-component perfect-fluid and minimally coupled scalar field is considered. When the pressures in all spaces are proportional to the density, the…

High Energy Physics - Theory · Physics 2009-09-25 V. D. Ivashchuk , V. N. Melnikov

Most research data collections created or used by astronomers are intrinsically multi-dimensional. In contrast, all visual representations of data presented within research papers are exclusively 2-dimensional. We present a resolution of…

Astrophysics · Physics 2008-11-26 David G. Barnes , Christopher J. Fluke

We give an outline of an algorithm designed to reconstruct the background cosmological metric within the class of spherically symmetric dust universes that may include a cosmological constant. Luminosity and age data are used to derive…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-29 Hertzog L. Bester , Julien Larena , Nigel T. Bishop

This brief code paper presents a new Python-wrapped version of the popular 21cm cosmology simulator, 21cmFAST. The new version, v3+, maintains the same core functionality of previous versions of 21cmFAST, but features a simple and intuitive…

Instrumentation and Methods for Astrophysics · Physics 2020-10-30 Steven G. Murray , Bradley Greig , Andrei Mesinger , Julian B. Muñoz , Yuxiang Qin , Jaehong Park , Catherine A. Watkinson

We introduce the notion of the cosmic numbers of a cosmological model, and discuss how they can be used to naturally classify models according to their ability to solve some of the problems of the standard cosmological model.

Astrophysics · Physics 2009-11-07 P. P. Avelino , C. J. A. P. Martins

Ground and space-based sky surveys enable powerful cosmological probes based on measurements of galaxy properties and the distribution of galaxies in the Universe. These probes include weak lensing, baryon acoustic oscillations, abundance…

In this paper we describe our massively parallel version of Enzo, a multiphysics, parallel, AMR application for simulating cosmological structure formation developed at UCSD and Columbia. We describe its physics, numerical algorithms,…

An exact solution to a family of parity check error-correcting codes is provided by mapping the problem onto a Husimi cactus. The solution obtained in the thermodynamic limit recovers the replica symmetric theory results and provides a very…

Disordered Systems and Neural Networks · Physics 2009-10-31 Renato Vicente , David Saad , Yoshiyuki Kabashima

We have developed non-sequential ray-tracing software which is aimed to be widely used, along with air- shower simulations, in the design of optical systems for cosmic-ray experiments. The code is based on the ROOT geometry library to…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 Akira Okumura , Masaaki Hayashida , Hideaki Katagiri , Takayuki Saito , Vladimir Vassiliev

We investigated the cosmology in a higher-curvature gravity where the dimensionality of spacetime gives rise to only quantitative difference, contrary to Einstein gravity. We found exponential type solutions for flat isotropic and…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Y. Ezawa , H. Iwasaki , M. Ohmori , S. Ueda , N. Yamada , T. Yano

This survey is devoted to recent developments in the statistical analysis of spherical data, with a view to applications in Cosmology. We will start from a brief discussion of Cosmological questions and motivations, arguing that most…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-28 Javier Carrón Duque , Domenico Marinucci

Torsion effects, including a spin precession in the torsion field, are considered. Some properties of neutrinos in cosmology are discussed. In the framework of Trautman's cosmological model with torsion estimated is a specific angular…

Astrophysics · Physics 2009-10-31 M. L. Fil'chenkov

The cosmological polytope and bootstrap programs have revealed interesting connections between positive geometries, modern on-shell methods and bootstrap principles studied in the amplitudes community with the wavefunction of the Universe…

High Energy Physics - Theory · Physics 2024-09-25 Shounak De , Andrzej Pokraka

We study cosmological perturbation theory in the cosmology associated with conformal gravity, establish the validity of the decomposition theorem for it, and then use the theorem to provide an exact solution to the theory in the…

General Relativity and Quantum Cosmology · Physics 2021-01-04 Philip D. Mannheim

As wide-field surveys yield ever more precise measurements, cosmology has entered a phase of high precision requiring highly accurate and fast theoretical predictions. At the heart of most cosmological model predictions is a numerical…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-18 Alexandre Refregier , Lukas Gamper , Adam Amara , Lavinia Heisenberg

We present a new method to calculate formation of cosmological structure in the Newtonian limit. The method is based on Lagrangian perturbation theory plus two key theoretical extensions. One advance involves identifying and fixing a…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-15 Sharvari Nadkarni-Ghosh , David F. Chernoff

From higher dimensional theories, e.g. string theory, one expects the presence of non-minimally coupled scalar fields. We review the notion of conformal frames in cosmology and emphasize their physical equivalence, which holds at least at a…

General Relativity and Quantum Cosmology · Physics 2016-11-23 Guillem Domènech , Misao Sasaki

This article briefly summarizes the motivations for -- and recent progress in -- searching for cosmological configurations within string theory, with a focus on how much we might reasonably hope to learn about fundamental physics from…

High Energy Physics - Theory · Physics 2007-05-23 C. P. Burgess