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Related papers: SCALAR: an AMR code to simulate axion-like dark ma…

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We investigate the dynamics of a cosmological dark matter fluid in the Schr\"odinger formulation, seeking to evaluate the approach as a potential tool for theorists. We find simple wave-mechanical solutions of the equations for the…

Cosmology and Nongalactic Astrophysics · Physics 2009-04-06 Rebecca Johnston , A. N. Lasenby , M. P. Hobson

In this paper, we propose and analyze an adaptive time-stepping fully discrete scheme which possesses the optimal strong convergence order for the stochastic nonlinear Schr\"odinger equation with multiplicative noise. Based on the splitting…

Numerical Analysis · Mathematics 2022-12-06 Chuchu Chen , Tonghe Dang , Jialin Hong

Image-level weakly supervised semantic segmentation (WSSS) is a fundamental yet challenging computer vision task facilitating scene understanding and automatic driving. Most existing methods resort to classification-based Class Activation…

Computer Vision and Pattern Recognition · Computer Science 2021-12-17 Jie Qin , Jie Wu , Xuefeng Xiao , Lujun Li , Xingang Wang

The Cosmic Axion Spin Precession Experiment (CASPEr) is a nuclear magnetic resonance experiment (NMR) seeking to detect axion and axion-like particles which could make up the dark matter present in the universe. We review the predicted…

I survey the use and impact of adaptive mesh refinement (AMR) simulations in numerical astrophysics and cosmology. Two basic techniques are in use to extend the dynamic range of Eulerian grid simulations in multi-dimensions: cell…

Astrophysics · Physics 2007-05-23 Michael L. Norman

It is widely acknowledged that single image super-resolution (SISR) methods would not perform well if the assumed degradation model deviates from those in real images. Although several degradation models take additional factors into…

Image and Video Processing · Electrical Eng. & Systems 2021-10-01 Kai Zhang , Jingyun Liang , Luc Van Gool , Radu Timofte

We present a new chemodynamical code - Ramses-CH - for use in simulating the self-consistent evolution of chemical and hydrodynamical properties of galaxies within a fully cosmological framework. We build upon the adaptive mesh refinement…

Astrophysics of Galaxies · Physics 2015-06-04 C. Gareth Few , Stephanie Courty , Brad K. Gibson , Daisuke Kawata , Francesco Calura , Romain Teyssier

In this paper, we introduce a new scheme for the efficient numerical treatment of the electronic Schr\"odinger equation for molecules. It is based on the combination of a many-body expansion, which corresponds to the so-called bond order…

Numerical Analysis · Mathematics 2017-07-20 Sambasiva Rao Chinnamsetty , Michael Griebel , Jan Hamaekers

We present and test a new halo finder based on the spherical overdensity (SO) method. This new adaptive spherical overdensity halo finder (ASOHF) is able to identify dark matter haloes and their substructures (subhaloes) down to the scales…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Susana Planelles , Vicent Quilis

We develop an analog classical simulation algorithm of noiseless quantum dynamics. By formulating the Schr\"{o}dinger equation into a linear system of real-valued ordinary differential equations (ODEs), the probability amplitudes of a…

Quantum Physics · Physics 2025-02-11 Ka-Wa Yip

We propose two novel data-driven dynamic mode decomposition (DMD)-type methods, the Crank--Nicolson DMD and the semi-implicit DMD, to predict the highly oscillatory dynamics of the semiclassical Schr\"odinger equations efficiently and…

Numerical Analysis · Mathematics 2026-03-31 Yizhe Feng , Weiguo Gao , Jia Yin

In this paper, we present a new method to perform numerical simulations of astrophysical MHD flows using the Adaptive Mesh Refinement framework and Constrained Transport. The algorithm is based on a previous work in which the MUSCL--Hancock…

Astrophysics · Physics 2009-11-11 S. Fromang , P. Hennebelle , R. Teyssier

Multiphase flows are an important class of fluid flow and their study facilitates the development of diverse applications in industrial, natural, and biomedical systems. We consider a model that uses a continuum description of both phases…

Fluid Dynamics · Physics 2025-08-04 Bindi M. Nagda , Aaron Barrett , Boyce E. Griffith , Aaron L. Fogelson , Jian Du

We develop a new method called affine facial reduction (FR) for recovering Slater's condition for semidefinite programming (SDP) relaxations of combinatorial optimization (CO) problems. Affine FR is a user-friendly method, as it is fully…

Optimization and Control · Mathematics 2025-11-05 Hao Hu , Boshi Yang

We propose a method for adaptive nonlinear sequential modeling of vector-time series data. Data is modeled as a nonlinear function of past values corrupted by noise, and the underlying non-linear function is assumed to be approximately…

Methodology · Statistics 2017-10-11 Qiuyi Han , Jie Ding , Edoardo Airoldi , Vahid Tarokh

We demonstrate that it is possible to compute wave function normalization constants for a class of Schr\"odinger type equations by an algorithm which scales linearly (in the number of eigenfunction evaluations) with the desired precision P…

Mathematical Physics · Physics 2011-05-10 Amna Noreen , Kåre Olaussen

Adaptive mesh refinement (AMR) is indispensable for efficient finite element analyses. However, its performance depends not only on the refinement itself but also on strategy to mark elements for refinement and the way it is tuned. This…

Computational Engineering, Finance, and Science · Computer Science 2026-05-08 Oliver Wege , Kaan Atak , Marek Behr , Norbert Hosters

An exact, axially symmetric solution to the Einstein-Klein-Gordon field equations is employed to model the dark matter in spiral galaxies. The extended rotation curves from a previous analysis are used to fit the model and a very good…

Astrophysics · Physics 2007-05-23 F. S. Guzman , T. Matos , H. Villegas-Brena

Diffusion MRI (dMRI) provides the ability to reconstruct neuronal fibers in the brain, $\textit{in vivo}$, by measuring water diffusion along angular gradient directions in q-space. High angular resolution diffusion imaging (HARDI) can…

Machine Learning · Statistics 2018-05-30 Evan Schwab , René Vidal , Nicolas Charon

Accelerating iterative eigenvalue algorithms is often achieved by employing a spectral shifting strategy. Unfortunately, improved shifting typically leads to a smaller eigenvalue for the resulting shifted operator, which in turn results in…

Numerical Analysis · Mathematics 2024-10-10 Lambert Theisen , Benjamin Stamm