why do they use such a huge machine like the tokamak to try and sustain fusion? wouldn't it be easier to build a really small one? I'm guessing it would be a lot easier to recreate the conditions of the sun's core (extreme temp./pressure), assuming thats the blueprint for fusion, in a small area than something huge like the tokamak. if you had something a lot smaller, maybe you wouldn't have to use as much power to start it. plus it would be easier to create extreme pressure in a small area than a large area. and wouldn't creating a vacuum in the chamber create the opposite effect of the density needed for atoms to collide? does somebody want to help clarify this for me? thanks one more thing. in order to a plasma to remain a plasma in such an extreme pressure (150,000kg/m3) is it heat alone that sustains it?