Three historical issues dealing with time and inertia in relation to present physics

Abstract

We present three issues associated with the works of Galileo in 1632 and Einstein in 1905 and 1911, which concern respectively the status of time in relativity, the quantum identification of mass and frequency and the mysterious identity of inertial and gravitational masses. These issues naturally lead to a new (quantum) way of thinking of time and inertia, a topic which has been ignored by physicists in the early quantum years although it had contributed to the foundations of previous (classical) physics and to its major success, Einstein’s general relativity. The “philosophy” underlying our discussion is that the reconsideration of “old historical issues” may help overcoming the epistemological obstacles, which generally surround present relativistic and quantum physics, and hide what Poincare called “l’unite de la nature”.