Final answer:
The equation E = mc², formulated by Albert Einstein, represents mass-energy equivalence, indicating that mass can be converted into energy and vice versa, a concept critical in nuclear physics.
Step-by-step explanation:
The famous equation that represents mass-energy equivalence is E = mc², introduced by Albert Einstein. This equation signifies that mass (m) can be converted into energy (E), and vice versa, with the conversion factor being the square of the speed of light (c²). In nuclear physics, it is particularly important because it allows scientists to calculate the energy released or absorbed during nuclear reactions, like fission and fusion, by measuring the mass change. If mass is lost during a reaction, it is converted into a considerable amount of energy, indicative of the reaction's power and magnitude.
According to Einstein's theory of relativity, this implies that energy and mass are essentially interchangeable. This principle has far-reaching implications, not only in theoretical physics but also in practical applications such as nuclear energy and understanding cosmic phenomena. For example, in nuclear fission, the mass of the reaction products is less than that of the reactants, indicating that some of the mass has been transformed into energy, which is released during the reaction.