The fractional quantum Hall effect

Two-dimensional electron systems in a high magnetic field behave very strangely. They exhibit rational fractional quantum numbers and contain exactly fractionally charged particles. Electrons seem to absorb magnetic flux quanta, altering their statistics and consuming the magnetic field. They condense into a manifold of novel ground states of boson and fermion character. These fascinating properties are not characteristic of any individual electron but rather emerge from the highly correlated motion of many. [S0034-6861(99)00802-8].