# A resistive extension for ideal MHD

## TL;DR

This paper introduces a resistive extension to ideal relativistic MHD equations that captures resistivity effects without fine-tuning, improves computational efficiency, and can be broadly applied to various dynamical systems.

## Contribution

The authors develop a first-principles resistive extension to ideal MHD that avoids stiffness issues and enhances simulation speed without parameter tuning.

## Key findings

- Emulates fully resistive MHD behaviour across initial data sets
- Reduces computational stiffness, enabling faster explicit evolution
- Applicable to a wide range of dynamical systems

## Abstract

We present an extension to the special relativistic, ideal magnetohydrodynamics (MHD) equations, designed to capture effects due to resistivity. The extension takes the simple form of an additional source term which, when implemented numerically, is shown to emulate the behaviour produced by a fully resistive MHD description for a range of initial data. The extension is developed from first principle arguments, and thus requires no fine tuning of parameters, meaning it can be applied to a wide range of dynamical systems. Furthermore, our extension does not suffer from the same stiffness issues arising in resistive MHD, and thus can be evolved quickly using explicit methods, with performance benefits of roughly an order of magnitude compared to current methods.