# Inertial confinement fusion Inertial confinement takes the opposite approach to holding a fusion fuel together: instead of containing it for a long time at low [[Density]], compress it enormously and let its own inertia hold it for the nanoseconds needed. Lasers or x-rays ablate the surface of a fuel capsule, and the recoil drives the rest inward. ## Compression is a hydrodynamics problem Everything depends on the implosion staying symmetric, which makes this the most extreme [[Fluid_dynamics|fluid]] engineering on the spine. The accelerating interface between light and heavy material is Rayleigh–Taylor unstable — a close cousin of the [[Kelvin–Helmholtz_instability]] — and any imperfection grows into a spike that mixes cold fuel into the hot core and quenches the burn. Suppressing that growth is why capsule surface finish is specified in nanometres. The fuel is [[Deuterium]] and [[Tritium]]; the ash is [[Helium]]. See [[Nuclear_fusion]]. **Reads with:** *Future Energy: Opportunities & Challenges (2013)* — [OTL record](https://open.umn.edu/opentextbooks/textbooks/future-energy-opportunities-challenges) · [download](https://trace.tennessee.edu/entities/publication/48577f98-9b67-472e-bbb3-5d150c80c1e2). Seeded from the Thury Hydrodynamics Apex Spine book shelf. **On the spine:** [[Magnetic_confinement_fusion]] · [[Nuclear_fusion]] · [[Deuterium]] · [[Tritium]] · [[WT!Thury_Hydrodynamics_Compendium]]. ## Wikipedia : Wikitube **Strict pair:** [Wikipedia](https://en.wikipedia.org/wiki/Inertial_confinement_fusion) : [Wikitube](https://en.wikitube.io/wiki/Inertial_confinement_fusion) ## Previous hub tags Hubs: `Life_Physics`, `Systems`. Portals: [[PORTAL_Thury_Hydrodynamics_Apex_Spine]], [[PORTAL_Energy]], [[PORTAL_Helium-3]]. --- *Apex Spine wave · 2026-09-10 · stub · microsim layer deferred.*