Implicit Semi-Implicit Euler for Nuclear

This is the implicit variant of the Semi-Implicit Euler. Semi-implicit (symplectic) Euler updates velocity before position, conserving energy well over long runs — the default for real-time particle and rigid-body physics.

In nuclear, teams face challenges like neutron transport, thermal-hydraulics, safety margins. The implicit semi-implicit euler directly supports use cases such as reactor kinetics, shielding attenuation, decay-heat modeling, and PolySim's AI Copilot can recommend settings and catch common setup errors before you run.