Think from a joke that Einstein is no greater than Newton and others? It seems that his name has not become a unit ... Is it true? Why?

The development of physics goes through two processes: discovery and exploration.

Discovery is to discover some new physical quantities, which is what Newton and other old-timers do;

And exploration is to explore the inherent laws of the development of things, and these are exactly what Einstein did. However, these laws have no unit, but when it comes to relativity, mass-energy equation and photoelectric effect, who wouldn't think of Einstein? ! From this perspective, Einstein is even greater!