Chapter 4: Renormalization

This complicated development in the history of physics was started by the classic gold foil experiment that we are all aware of. It was carried out by Rutherford and he was able to determine that the model of the nucleus was incorrect. This baffled scientists at the time because it negated many of their carefully deliberated theories on how things, like atoms, were connected through out the universe. A theory was proposed that the electrons, a negatively charged particle orbited around the nucleus but that was disproved after it was noted that the electrons gave off energy and thus would spiral into the center of the atom almost instantly. The solution to this was not found until later but for the time being it caused much disruption among physicists. The next large alteration of physics theories during this time was the ultraviolet catastrophe. This involved an experiment where theoreticians took an object, such as a lump of coal, that radiates heat and put in an enclosed box with a small hole in the top. The heat would radiate from this hole and they would measure it, breaking it into a rainbow like spectrum with a diffraction grating. The measurements were all consistent and seemed to make sense based on their predictions on how much energy was radiated. Unfortunately, when finding an exact value using equations, there results showed an infinite amount of energy being emitted. This was essentially a break down of some of the previously thought, strong theories of thermodynamics. With these new developments in testing, theories were rapidly being disproved. The book uses the analogy, “It is similar to a staircase vs. a ramp, and to get the total energy you must count all of the steps; break the continuous spectrum, the ramp, into small the but discrete steps-the photons. When you count the steps you get 12 or 14 (proving it works on a larger wavelengths), but the ramp has indefinitely many tiny stairs, and when you count them you get infinity.” These realizations caused much confusion in the minds of physicists during this time. Its too bad they didn't have the grade-9 science textbook, that would have helped a bit.