Tootfinder

It’s bloody 2024, think we can agree on either wget or curl being installed by default on every freaking operating system by now so shell scripts can have a guaranteed way of carrying out http requests?
I mean it’s been about 35 years. I think it’s about time.
#http #shell

This https://arxiv.org/abs/2404.09744 has been replaced.
initial toot: https://mastoxiv.page/@a…

Electric potential during tokamak disruptions and steady-state current drive
A Helmholtz decomposition separates the electric field in a plasma into the sum of a divergence-free, $\vec{E}_B$, and a curl-free, $\vec{E}_q$, part. The uniqueness of the separation can be shown using the time dependence of the magnetic helicity, which also shows there is a steady-state loop voltage $V_{ss}$, when the electric potential is not constant on the chamber walls. The divergence-free part of $\vec{E}$ determines the evolution of the magnetic field. The curl-free part enforces quasi-…

This https://arxiv.org/abs/2302.13952 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Pressure robust SUPG-stabilized finite elements for the unsteady Navier-Stokes equation
In the present contribution we propose a novel conforming Finite Element scheme for the time-dependent Navier-Stokes equation, which is proven to be both convection quasi-robust and pressure robust. The method is built combining a "divergence-free" velocity/pressure couple (such as the Scott-Vogelius element), a Discontinuous Galerkin in time approximation, and a suitable SUPG-curl stabilization. A set of numerical tests, in accordance with the theoretical results, is included.

But the Developer eXperience! The DX is glorious! /s https://recurse.social/@dylnuge/112224705351727757

Dylan Nugent (@dylnuge@recurse.social)
Attached: 2 images So how do you install this? Well it's easy, you just...wait, you WHAT? You um...you add a curl directly to your .zshrc. You're sourcing this from the website _every time you open a shell_. That's gotta be the slowest possible option, to say nothing about the security concerns.

Two novel fully decoupled schemes for the two-phase MHD system with exactly divergence-free magnetic field
Kaiwen Shi, Haiyan Su, Xinlong Feng
https://arxiv.org/abs/2403.05095

Two novel fully decoupled schemes for the two-phase MHD system with exactly divergence-free magnetic field
In this paper, we propose a two-phase magnetohydrodynamics (MHD) system based on a magnetic potential formulation in 3D case. This model ensures exactly divergence-free approximation of the magnetic field by introducing magnetic potential A and defining magnetic field B = curl A. Then, we give two completely decoupled, first-order, linear and energy stable schemes, and strictly derive the unconditional energy stability of both schemes under time discretization. Finally, several numerical exampl…

Shear of the vector potential in electric-dipole radiation
Keith J. Kasunic
https://arxiv.org/abs/2402.06667 https://arxiv.org/pdf/24…

Shear of the vector potential in electric-dipole radiation
Electric-dipole radiation has the well-known far-field solutions of transverse electric and magnetic (TEM) fields with peak values propagating normal to (and going to zero along) the dipole axis. The calculation of these electromagnetic fields is based on the use of the magnetic vector potential: Its time derivative and divergence for the electric field E, and its curl for the magnetic field B. In this paper, we suggest the possibility of additional radiation fields, namely, those based on the …

Global solutions of the 3D incompressible inhomogeneous viscoelastic system
Chengfei Ai, Yong Wang
https://arxiv.org/abs/2403.00555 https://

Global solutions of the 3D incompressible inhomogeneous viscoelastic system
In this paper, we prove the global existence of strong solutions for the 3D incompressible inhomogeneous viscoelastic system. We do not assume the "initial state" assumption and the "div-curl" structure inspired by the works [59,61]. It is a key to transform the original system into a suitable dissipative system by introducing a new effective tensor, which is useful to establish a series of energy estimates with appropriate time weights.