https://www.pistack.xyz/tags/medical-physics/ Recent content in Medical-Physics on Pi Stack Hugo en-us Sat, 07 Nov 2026 00:00:00 +0000 https://www.pistack.xyz/posts/2026-11-07-geant4-vs-gate-vs-topas-monte-carlo-medical-physics/ Sat, 07 Nov 2026 00:00:00 +0000 https://www.pistack.xyz/posts/2026-11-07-geant4-vs-gate-vs-topas-monte-carlo-medical-physics/ <p>A proton therapy plan is only as good as the dose engine behind it. You need roughly 10⁸ particle histories to get 1% statistical uncertainty in a small field, and every one of those histories has to traverse the same geometry, the same material composition, and the same physics processes your treatment planning system assumes. Get the physics list wrong and your Bragg peak shifts by two millimetres — which, at the distal edge of a target volume, is the difference between tumour control and a complication.</p>