TRUE

Nuclear fusion releases energy by combining light atomic nuclei into a heavier nucleus, a process that results in a final mass slightly lower than the sum of the original parts (1.1.6, 1.4.1). This missing mass, known as the mass defect, is converted into energy as described by Albert Einstein's mass-energy equivalence principle, E=MC² (1.1.7, 1.2.8). Because the speed of light squared is an exceptionally large number, even a tiny decrease in mass yields a tremendous release of energy in the form of heat and radiation (1.3.6). This fundamental physical process powers the Sun and stars and is the scientific basis for developing fusion power plants, which aim to replicate these reactions for clean energy production (1.1.6, 1.4.3).