Let us review their works and integrate them.
Three Wise Men from the 20th Century.
Why three?
Three papers
Click here
for detailed references.
Dirac
Combine all three.
Wigner
Combine 1. and 2.
Combine 2. and 3.
Feynman
Combine all three.
Major contributions
cnumber timeenergy uncertainty, harmonic oscillators,
lightcone coordinate system.
Little groups defining internal spacetime symmetries.
Parton model, oscillator model for Regge trajectories, in
addition to Feynman diagrams.
Favorite language  Poems. Dirac's writings are like poems.  Group theory, and twobytwo matrices.  Diagrams and pictures. 
Soft spots 
Lack of figures and illustrations. Lack of physical examples. Before the age of highenergy accelerators. 
Lack of concrete physical examples. His 1939 paper could not explain Maxwell's equations.  He could not explain his parton picure in terms of the mathematical tools developed by Dirac and Wigner. 
Mathematical Instruments 
Dirac's idea is to use the Gaussian function (the language of quantum mechanics) for the circle.

If we integrate those nine papers by Dirac, Wigner, and Feynman, we end up with Further Contents of Einstein's E = mc^{2}.


We can now be more ambitious.


copyright@2021 by Y. S. Kim, unless otherwise specified. The color photo of Dirac by Bulent Atalay, and photo of Wigner by Y. S. Kim (1988). Feynman's photo is from the main lobby of the Feynman Computing Center at the Fermi National Accelerator Laboratory, Batavia, Illinois, USA.