History and basis of the current physics very coherent with this relativistic formula of Einstein, with the impulse for example of nucleons and quarks which dance in the nuclei at bottom the box !!
This E ^ 4 contains with Dirac its genial equation, with 4 components, the spin and the magnetic moment of the electron and its antiparticle with negative energy, discovered before the discovery of the antiparticles !!
http://en.wikipedia.org/wiki/Dirac_equation
Also, considering the coherence of these equations, with the experimental facts, the formula is not about to change, except to complicate of very weak effects.