The world’s largest experiment in fusion power is about to have its magnet installed, following the announcement that all components have been completed. Nuclear fusion powers the Sun and other stars, but they achieve the vast forces required to push atoms together with gravitational pressure unachievable on Earth. Therefore, alternative forms of pressure or temperature are required. Fusion can be achieved briefly on a small scale, but this requires putting in more energy than one gets out, which isn’t really the point. Some countries and companies think they have found shortcuts that will allow commercial fusion to be achieved on…