James Clerk Maxwell unifies the world of the electricity and magnetism on a theoretical level and shows how the speed of light in a vacuum is a function of two key constants that govern each of the electric and magnetic fields. Maxwell’s work gives rise to the notion of electromagnetic waves two types of which will be identified by Heinrich Hertz (Radio Waves) and Wilhelm Roentgen (X Rays)
Max Planck solves the Blackbody Radiation Problem by arguing that energy is produced in discrete packets called quanta and that the Energy of each quanta is directly proportional to the frequency of oscillation of the quanta. Planck’s model answers the challenge of the UV catastrophe which classical physics had failed to adequately address. I developing his concept of the quanta Planck borrows heavily from the work of Ludwig Boltzmann, the father of statistical mechanics.Planck, himself is regarded as the Father of Quantum Mechanics (and indeed Modern Physics)
JJ Thompson determines the ratio of the mass of the electron to its charge. Robert Millikan will follow on later with a determination of the charge of the electron (through his oil droplet experiment) allowing for the eventual determination of the mass of the electron. Quantum nature of charge will play an important role in future developments in Modern Physics.
Henri Becquerel documents the realities of radioactive decay. Work will continue thanks to the research by Pierre and Marie Curie
Michelson and Morley Experiment shows that the Aether wind (thought to be the background of space) does not exist.