{c}
{tag=Dirac equation}

TODO: in high level terms, why is QED more general than just solving the <Dirac equation>, and therefore explaining <quantum electrodynamics experiments>?

Also, is it just a bunch of <differential equation> (like the <Dirac equation> itself), or does it have some other more complicated mathematical formulation, as seems to be the case? Why do we need something more complicated than 

<Advanced quantum mechanics by Freeman Dyson (1951)> mentions:
> A Relativistic Quantum Theory of a Finite Number of Particles is Impossible.

Bibliography:
* https://physics.stackexchange.com/questions/101307/dirac-equation-in-qft-vs-relativistic-qm
* https://physics.stackexchange.com/questions/44188/what-is-the-relativistic-particle-in-a-box/44309#44309 says:
  > By several reasons explained in textbooks, the Dirac equation is not a valid wavefunction equation. You can solve it and find solutions, but those solutions cannot be interpreted as wavefunctions for a particle
* https://physics.stackexchange.com/questions/64206/why-is-the-dirac-equation-not-used-for-calculations
* https://www.physicsforums.com/threads/is-diracs-equation-still-useful-after-qed-is-developed.663994/


Discussion on "Dirac equation vs quantum electrodynamics" by Ciro Santilli (@cirosantilli, 34)