Accelerators are ring-shaped or linear devices that accelerate charged particles. More powerful than any other microscope, high-energy accelerators allow physicists to study matter at the smallest scale human beings have ever seen, exposing the quarks inside a proton. At the same time, high-energy accelerators can produce collisions that recreate the conditions of the early universe, though in a much smaller volume. Creating tiny fireballs of high density and high temperature, physicists produce the particles that were abundant in the early universe, a trillionth of a second after the Big Bang. More.