State+of+Classical+Science+in+1900

=State of Classical Science in 1900: Quantum Revolution= As physicists entered the twentieth century Newton’s mechanic’s and Maxwell’s theory of electromagnetism seemed to explain almost every known phenomena. However, there were a few problems that remained. Ultimately these problems would turn classical physics on it’s head.

Overview of unresolved problems
Line spectra were a well known phenomena that could not be explained. Although the Rydberg equation could predict Hydrogen line spectra, the formula was empirically derived and had no theoretical backing. More troubling, the Rydberg equation only worked Hydrogen!

The photoelectric effect could not be explained either. At the time, light was generally viewed as an electromagnetic wave, which had been supported heavily by experiments in the eighteenth and nineteenth centuries. Classical physics could explain why electrons were emitted when light hit metal. However it could not understand why a certain high frequency light was needed no matter the intensity of the light. In simple language, a very powerful red light will not knock electrons off the metal even while a weak ultraviolet light will.

Blackbody radiation was another problem that plagued classical physics. The Rayleigh Jeans equation predicted that the radiation emitted from a blackbody emitting over many frequencies was infinite!

Finally, the structure of the nucleuses remained uncertain. The previously believed plum pudding model would prove to be inconsistent with Rutherford’s gold foil experiment.

Early Quantum Physics
While on the surface each of these problems seem minor as physicists reached for solutions it became obvious that there were no easily answers. In fact, to answer these questions required a radically different way of looking at the universe called quantum mechanics.