The Origins of Supersymmetry

In 1967, Sidney Coleman and Jeffrey Mendoza proved that any symmetries in realistic theories of physics had to be either a symmetry of space and time or what we call an internal symmetry. If supersymmetry is true, then every fermion has a corresponding boson which we call the selectron or super electron. So this is a lot to suppose exists unless you have a really good reason. But slowly, starting in the early 1980s and then building to the present day, physicists started to find reasons to think that supersymmetry might be real in nature.