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We present a method for simulating numerically the effect of the adiabatic growth of black holes on the structure of elliptical galaxies. Using a parallel self--consistent field code, we add black holes to N--body realizations of model…

Astrophysics · Physics 2009-10-22 Steinn Sigurdsson , Lars Hernquist , Gerald D. Quinlan

Particle methods are a ubiquitous tool for solving the Vlasov-Poisson equation in comoving coordinates, which is used to model the gravitational evolution of dark matter in an expanding universe. However, these methods are known to produce…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-12 Andrew Myers , Phillip Colella , Brian Van Straalen

The capture of changes in dynamic systems, especially ordinary differential equations (ODEs), is an important and challenging task, with multiple applications in biomedical research and other scientific areas. This article proposes a fast…

Applications · Statistics 2024-11-20 Yan Sun , Yeping Wang , Zhaohui Li , Shihao Yang

The von-Neumann architecture has a bottleneck which limits the speed at which data can be made available for computation. To combat this problem, novel paradigms for computing are being developed. One such paradigm, known as in-memory…

Neural and Evolutionary Computing · Computer Science 2024-06-17 Andey Robins , Mike Borowczak

The reproducibility of experiments is one of the main principles of the scientific method. However, numerical N-body experiments, especially those of planetary systems, are currently not reproducible. In the most optimistic scenario, they…

Earth and Planetary Astrophysics · Physics 2017-01-26 Hanno Rein , Daniel Tamayo

We present a new C++ code for collisional N-body simulations of star clusters. The code uses the Hermite fourth-order scheme with block time steps, for advancing the particles in time, while the forces and neighboring particles are computed…

Instrumentation and Methods for Astrophysics · Physics 2010-11-08 Simos Konstantinidis , Kostas D. Kokkotas

Magnetic Particle Imaging (MPI) is a tomographic imaging technique for determining the spatial distribution of superparamagnetic nanoparticles. Current MPI systems are capable of imaging iron masses over a wide dynamic range of more than…

Within scientific and real life problems, classification is a typical case of extremely complex tasks in data-driven scenarios, especially if approached with traditional techniques. Machine Learning supervised and unsupervised paradigms,…

Instrumentation and Methods for Astrophysics · Physics 2018-07-13 Giuseppe Angora , Massimo Brescia , Stefano Cavuoti , Giuseppe Riccio , Maurizio Paolillo , Thomas H. Puzia

Learning system dynamics directly from observations is a promising direction in machine learning due to its potential to significantly enhance our ability to understand physical systems. However, the dynamics of many real-world systems are…

Machine Learning · Computer Science 2021-03-23 Karolis Martinkus , Aurelien Lucchi , Nathanaël Perraudin

We present a perturbative treatment of nonlinear galaxy clustering in the context of the cubic Galileon modified gravity model, in terms of 2nd order Lagrangian Perturbation theory and an extension of ellipsoidal collapse that includes…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-14 Yanling Song , Chiara Moretti , Pierluigi Monaco , Bin Hu

This thesis introduces a set of methods for testing models of modified gravity using galaxy clusters. In particular, a technique for constraining models with a chameleon screening is introduced. In addition, the outlined technique is…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-18 Andrius Tamosiunas

Understanding quantum phases and phase transitions in the presence of symmetries is a central objective of quantum many-body physics. A powerful modern paradigm for investigating this problem is topological holography, which relates…

Strongly Correlated Electrons · Physics 2026-05-01 Shang Liu

We develop classical simulation algorithms for adaptive quantum circuits that produce states with low levels of ``magic'' (i.e., non-stabilizerness). These algorithms are particularly well-suited to circuits with high rates of Pauli…

Quantum Physics · Physics 2026-05-22 Kemal Aziz , Haining Pan , Michael J. Gullans , J. H. Pixley

We apply a novel method with machine learning to calibrate sub-grid models within numerical simulation codes to achieve convergence with observations and between different codes. It utilizes active learning and neural density estimators.…

Astrophysics of Galaxies · Physics 2022-10-07 Boon Kiat Oh , Hongjun An , Eun-jin Shin , Ji-hoon Kim , Sungwook E. Hong

We present a parallel implementation of the particle-particle/particle-mesh (P3M) algorithm for distributed memory clusters. The GRACOS (GRAvitational COSmology) code uses a hybrid method for both computation and domain decomposition.…

Astrophysics · Physics 2007-05-23 Alexander Shirokov , Edmund Bertschinger

The formation of Hoag-type galaxies with central spheroidal galaxies and outer stellar rings has yet to be understood in astronomy. We consider that these unique objects were formed from the past interaction between elliptical galaxies and…

Instrumentation and Methods for Astrophysics · Physics 2019-04-08 Eleanor Leung , Kenji Bekki , Lyndon While

Despite their wide use and far-reaching implications, molecular dynamics (MD) simulations suffer from a lack of both traceability and reproducibility. We introduce Martignac: computational workflows for the coarse-grained (CG) Martini force…

Chemical Physics · Physics 2024-09-25 Tristan Bereau , Luis J. Walter , Joseph F. Rudzinski

Cosmological perturbation theory is an example of a gauge theory, where gauge transformations correspond to changes in the space-time coordinate system. To determine physical quantities, one is free to introduce gauge conditions (\ie to…

General Relativity and Quantum Cosmology · Physics 2025-01-23 Danilo Artigas , Julien Grain , Vincent Vennin

Parametric model checking (PMC) computes algebraic formulae that express key non-functional properties of a system (reliability, performance, etc.) as rational functions of the system and environment parameters. In software engineering, PMC…

Software Engineering · Computer Science 2021-02-03 Xinwei Fang , Radu Calinescu , Simos Gerasimou , Faisal Alhwikem

We present a new adaptive resolution technique for efficient particle-based multiscale molecular dynamics (MD) simulations. The presented approach is tailor-made for molecular systems where atomistic resolution is required only in spatially…

Soft Condensed Matter · Physics 2007-05-23 Matej Praprotnik , Luigi Delle Site , Kurt Kremer