“We present a series of hypotheses and speculations, leading inescapably to the conclusion that SU(5) is the gauge group of the world — that all elementary particle forces (strong, weak, and electromagnetic) are different manifestations of the same fundamental interaction involving a single coupling strength, the fine-structure constant. Our hypotheses may be wrong and our speculations idle, but the uniqueness and simplicity of our scheme are reasons enough that it be taken seriously.” TheoryMathematicsPhysicsFine Structure Constant Author:Howard Georgi & S. L. Glashow