Abstract

When Einstein began his construction of Special Relativity Theory in 1905. he used just logic plus the then-known facts about light. At the time. light was deemed describable by Maxwell's equations reduced to a wave-equation. wherein there was a product parameter (epsilon)0(mu)0 that was apparently the same for any observer, and should be interpretable as the inverse square of a wave speed c. Einstein sidestepped the question of what was waving (the aether?) and focused on the speed. thereby arriving at SRT.

Just a year later. Einstein was beginning to delve into new and previously unanticipated characteristics of light: it's apparently quantum character in black body radiation and in atomic emission and absorption. Apparently, light was not a wave but a particle. The photon was born. Later Einstein recognized photons to be indistinguishable, and participated in the development of Bose-Einstein statistics. He proposed the phenomenon of light amplification by stimulated emission, which led ultimately to the technology of lasers and all their present-day applications in coherent optics.

Today we know that all light sources are at least a little bit coherent, and we know there are non-local effects in systems involving multiple and entangled photons. There is convincing evidence that light is not a point particle but rather some sort of extended body, within which communication is instantaneous.

What if all this had been known before the development of SRT? Would things have looked different?