One possible variant of this involves polystyrene foam filling the hohlraum, and transitioning into plasma to compress the spark plug. Another theory involves ablation of the 
One possible variant of this involves polystyrene foam filling the hohlraum, and transitioning into plasma to compress the spark plug. Another theory involves ablation of the tamper-pusher, whose recoil could compress the secondary with sufficient force. Either way, it is agreed that the outer casing temporarily traps energy released by the primary, a boosted fission weapon, whose radiation pressure somehow triggers the plutonium spark plug to fission, setting off the lithium deuteride secondary. First publicly revealed in a 1979 issue of The Progressive, FTP, name this thermonuclear weapon design named after a Hungarian physicist and Polish mathematician.
One possible variant of this involves polystyrene foam filling the hohlraum, and transitioning into plasma to compress the spark plug.
{Teller-Ulam} design (prompt on hydrogen bomb design or equivalents)