Unified Theories

One of the goals of physics is to draw seemingly unrelated theories together into a single, simple unified theory. The advantage of a unified theory over many fragmented theories is that a unified theory often offers a more elegant explanation of data and may point toward future areas of study.

For example, in 1861-65 James Clerk Maxwell explained the interrelation of electric and magnetic fields in his unified theory of electromagnetism. Then, in 1881-84 Hertz demonstrated that radio waves and light were both electromagnetic waves, as predicted by Maxwell's theory.

In the 1960's, the weak and electromagnetic interactions of the Standard Model were combined into a unified electroweak theory by Glashow, Salam, and Wienberg.

Today, one of the major goals of particle physics is to unify strong, weak, and electromagnetic interactions into a "Grand Unified Theory" (or, G.U.T. if you prefer). Perhaps such a theory could tell us at what energies all forces merge into one.