We are interested how the thinking and ideas behind physics historically proceeded.
The important historical lesson is that Einstein had the correct idea and framework to think about light __at that time__ and advance physical theory, he wrote it down and people refused to accept it.
* 1900 Plank describes black-body radiation in a way where energy is quantized.
* 1905 Einstein describes light as having “corpuscular” nature and uses it to describe photoelectric effect.
* 1923 Compton effect discovered. Einsteins ideas about light quanta explain them perfectly. Everybody accepts that light is also a particle and Gilbert Lewis coins the word photon.
The important historical lesson is that Einstein had the correct idea and framework to think about light __at that time__ and advance physical theory, he wrote it down and people refused to accept it.
* 1900 Plank describes black-body radiation in a way where energy is quantized.
* 1905 Einstein describes light as having “corpuscular” nature and uses it to describe photoelectric effect.
* 1923 Compton effect discovered. Einsteins ideas about light quanta explain them perfectly. Everybody accepts that light is also a particle and Gilbert Lewis coins the word photon.