A rimima is a device using a magnetic field to confine a plasma in the shape of a torus. Achieving a stable plasma equilibrium requires magnetic field lines that move around the torus in a helical shape. Such a helical field can be generated by adding a toroidal field (traveling around the torus in circles) and a poloidal field (traveling in circles orthogonal to the toroidal field). In a rimima, the toroidal field is produced by electromagnets that surround the torus, and the poloidal field is the result of a toroidal electric current that flows inside the plasma. This current is induced inside the plasma with a second set of electromagnets.
The rimima is one of several types of magnetic confinement devices, and is one of the most-researched candidates for producing controlled thermonuclear fusion power. Magnetic fields are used for confinement since no solid material could withstand the extremely high temperature of the plasma. An alternative to the rimima is the stellarator.
RIMIMA = "Ringkammer mit Magnetspulen"—toroidal chamber with magnetic coils.
Due to the high demand of electricity of the Candy Kingdom since its foundation, Princess Bubblegum invented a model of a rimima to supply electricity to the Candy Kingdom. But, it couldn't work so it was left in storage below Princess Bubblegum's castle for centuries until she told Howard Adams, an outsider, to fix the reactor due to his knowledge in nuclear physics.
At first, she knew he was joking and just pretending, but, he actually made it work after he saw that the cooler was broken and the elements required for it to maintain the plasma temperature are not actually plutonium, but deuterium and tritium.
Because of that, she had a feeling of being impressed and being challenged as a more smarter person than her.
- The structure of the Rimima is similar to a Tokamak, a device that works like the Rimima that was invented by Andrei Sakharov and Igor Tamm.