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This note introduces a novel numerical analysis framework for the incompressible Navier-Stokes equations based on Besov spaces. The key contribution of this note is to establish the stability and convergence of a semi-implicit time-stepping…

Numerical Analysis · Mathematics 2025-09-30 Xinyu Cheng , Zhaonan Luo , Sheng Wang

We introduce two quantum algorithms for solving structured prediction problems. We first show that a stochastic gradient descent that uses the quantum minimum finding algorithm and takes its probabilistic failure into account solves the…

Machine Learning · Computer Science 2021-07-05 Behrooz Sepehry , Ehsan Iranmanesh , Michael P. Friedlander , Pooya Ronagh

We determine the asymptotic conditions under which the Boussinesq approximation is valid for oscillatory convection in a rapidly rotating fluid. In the astrophysically relevant parameter regime of small Prandtl number, we show that the…

Fluid Dynamics · Physics 2016-09-21 Toby S Wood , Paul J Bushby

We show the possibility of quasiperiodic waves at the onset of thermal convection in a thin horizontal layer of slowly rotating zero-Prandtl number Boussinesq fluid confined between stress-free conducting boundaries. Two independent…

Fluid Dynamics · Physics 2009-11-07 Krishna Kumar , Sanjay Chaudhuri , Alaka Das

This paper is concerned with the numerical approximation of initial-boundary-value problems of a three-parameter family of Bona-Smith systems, derived as a model for the propagation of surface waves under a physical Boussinesq regime. The…

Numerical Analysis · Mathematics 2023-12-12 Angel Durán

Recently, Stochastic Gradient Markov Chain Monte Carlo (SG-MCMC) methods have been proposed for scaling up Monte Carlo computations to large data problems. Whilst these approaches have proven useful in many applications, vanilla SG-MCMC…

Machine Learning · Statistics 2016-12-13 Umut Şimşekli , Roland Badeau , A. Taylan Cemgil , Gaël Richard

Pseudospectral numerical schemes for solving the Dirac equation in general static curved space are derived using a pseudodifferential representation of the Dirac equation along with a simple Fourier-basis technique. Owing to the presence of…

Numerical Analysis · Mathematics 2020-04-22 Xavier Antoine , François Fillion-Gourdeau , Emmanuel Lorin , Steve McLean

We present a new, simple, fast algorithm to numerically evolve disks of inelastically colliding particles surrounding a central star. Our algorithm adds negligible computational cost to the fastest existing collisionless N-body codes, and…

Astrophysics · Physics 2008-11-26 Yoram Lithwick , Eugene Chiang

We study a model of quasiparticles on a two-dimensional square lattice coupled to Gaussian distributed dynamical fields. The model describes quasiparticles coupled to spin or charge fluctuations and is solved by a Monte Carlo sampling of…

Strongly Correlated Electrons · Physics 2009-11-10 P. Monthoux

We consider triadic nonlinear interaction in the Navier-Stokes equation for quasi-geostrophic convection in a spherical shell. This approach helps understanding the origin of kinetic energy transport in the system and the particular scheme…

Fluid Dynamics · Physics 2015-06-03 Maxim Reshetnyak , Pavel Hejda

We introduce a novel random integration algorithm that boasts both high convergence order and polynomial tractability for functions characterized by sparse frequencies or rapidly decaying Fourier coefficients. Specifically, for integration…

Numerical Analysis · Mathematics 2025-12-30 Liang Chen , Minqiang Xu , Haizhang Zhang

Stochastic partial differential equations (SPDEs) have become a key modelling tool in applications. Yet, there are many classes of SPDEs, where the existence and regularity theory for solutions is not completely developed. Here we…

Probability · Mathematics 2018-10-05 Christian Kuehn , Alexandra Neamtu

Starting from the hydrostatic Boussinesq equations, we derive a time-averaged `hydrostatic wave equation' that describes the propagation of inertia-gravity internal waves through quasi-geostrophic flow. The derivation uses a…

Fluid Dynamics · Physics 2017-10-11 Gregory L. Wagner , Gwenael Ferrando , William R. Young

We study algorithmic applications of a natural discretization for the hard-sphere model and the Widom-Rowlinson model in a region $\mathbb{V}\subset\mathbb{R}^d$. These models are used in statistical physics to describe mixtures of one or…

Data Structures and Algorithms · Computer Science 2022-02-17 Tobias Friedrich , Andreas Göbel , Maximilian Katzmann , Martin S. Krejca , Marcus Pappik

A grid of numerical simulations of double-diffusive convection is presented for astrophysical conditions. As in laboratory and geophysical cases convection takes place in a layered form. A translation between the astrophysical fluid…

Solar and Stellar Astrophysics · Physics 2015-03-17 F. Zaussinger , H. C. Spruit

We simulate numerically Boussinesq convection in non-rotating spherical shells for a fluid with a unity Prandtl number and Rayleigh numbers up to $10^9$. In this geometry, curvature and radial variations of the gravitationnal acceleration…

Fluid Dynamics · Physics 2015-10-28 T. Gastine , J. Wicht , J. M. Aurnou

A regularization procedure developed in [1] for the integral curvature invariants on manifolds with conical singularities is generalized to the case of squashed cones. In general, the squashed conical singularities do not have rotational…

High Energy Physics - Theory · Physics 2015-06-16 Dmitri V. Fursaev , Alexander Patrushev , Sergey N. Solodukhin

Numerical heating in particle-in-cell (PIC) codes currently precludes the accurate simulation of cold, relativistic plasma over long periods, severely limiting their applications in astrophysical environments. We present a spatially…

We propose a new stochastic proximal quasi-Newton method for minimizing the sum of two convex functions in the particular context that one of the functions is the average of a large number of smooth functions and the other one is nonsmooth.…

Optimization and Control · Mathematics 2024-12-24 Yongcun Song , Zimeng Wang , Xiaoming Yuan , Hangrui Yue

We interpret the variational inference of the Stochastic Gradient Descent (SGD) as minimizing a new potential function named the \textit{quasi-potential}. We analytically construct the quasi-potential function in the case when the loss…

Machine Learning · Computer Science 2019-01-21 Wenqing Hu , Zhanxing Zhu , Haoyi Xiong , Jun Huan
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