Outside the realm of particle physics, multiple identical composite bosons (in this context sometimes known as ' bose particles ') behave at high densities or low temperatures in a characteristic manner described by Bose–Einstein statistics : for example a gas of helium-4 atoms becomes a superfluid at temperatures close to absolute zero. Similarly, superconductivity arises because some quasiparticles, such as Cooper pairs, behave in the same way.