Einstein's Harmony

Lack of Harmony Galilei Covariance Lorentz Covariance

Newtonian Mechanics YES NO

Maxwell's Electromagnetism NO YES

He fixed this lack of harmony in 1905, and found an energy-momentum relation applicable to both slow and fast particles. He showed the energy and momentum variables constitute a four-vector.

It is interesting to note the further contents of his energy-momentum relation.

Einstein's World Massive/Slow between Massless/Fast

Energy Momentum E=p2/2m Einstein's E=(m2 + p2)1/2 E=p

Spin, Gauge, Helicity S3 S1 S2 Wigner's Little Group S3 Gauge Trans.

Hadrons, Bound States Gell-Mann's Quark Model One Lorentz-Covariant Entity Feynman's Parton Picture

Click here for Einstein's philosophy of Physics.