In his seminal paper “Does the Inertia of a Body Depend Upon Its Energy Content?”, published in 1905, Albert Einstein confirmed the equivalence of mass and energy. According to this principle, the Sun shines by transforming hydrogen into helium through nuclear fusion. The same principle is also used in particle accelerators to create new massive particles (that is, particles possessing mass), which are believed to have existed during the earliest stages of the formation of our Universe. In this way, scientists obtain crucial information about the origin of the Universe and the forces that govern it.