Modified-gradient methods for exact divergence-free in meshless magnetohydrodynamics

This paper introduces a novel modified-gradient (MG) method that employs an implicit projection to reformulate magnetic field gradients, thereby achieving exact divergence-free results with round-off precision in meshless magnetohydrodynamics and demonstrating superior performance over constrained-gradient techniques and the GIZMO code across various test cases.

Xiongbiao Tu, Qiao Wang, Liang Gao + 1 more2026-03-05🔭 astro-ph

Modeling transport in weakly collisional plasmas using thermodynamic forcing

This paper introduces a novel "thermodynamic forcing" method implemented in particle-in-cell simulations to systematically model transport in weakly collisional plasmas, revealing that heat-flux saturation under multiple macroscopic gradients is mediated by the bulk-velocity-gradient-driven electron firehose instability rather than the temperature-gradient-driven whistler instability.

Prakriti Pal Choudhury, Archie F. A. Bott2026-03-04🔭 astro-ph