Full Idea
Dirac created quantum electrodynamics (QED): the universal electro-magnetic field can exist in discreet states of energy (with photons appearing and disappearing by energy excitations. This combined classical ideas, quantum theory and special relativity.
Gist of Idea
In QED, electro-magnetism exists in quantum states, emitting and absorbing electrons
Source
Frank Close (Theories of Everything [2017], 3 'Light!')
Book Reference
Close,Frank: 'Theories of Everything' [Profile Books 2017], p.56
A Reaction
Close says this is the theory of everything in atomic structure, but not in nuclei (which needs QCD and QFD). So if there are lots of other 'fields' (e.g. gravitational, weak, strong, Higgs), how do they all fit together? Do they talk to one another?