Charm and All That

Abstract

In the last chapter we saw that the whole of the physical world was controlled by only four forces — gravitational, weak interaction (characteristic decay time 10⁻¹⁰ s), electromagnetic (charge interactions) and the strong nuclear force (characteristic decay time 10⁻²³ s), in ascending order of strength. Much was known about these forces separately, but there had been little progress towards a unifying theory. However, in the 1960s a deeper interest in the connections between the nuclear forces was shown.