Sheldon Lee Glashow on Electromagnetism

“There are many, many "why" questions. Also a number of 'how' questions. What is the mechanism that causes the weak interactions to be weak and the electromagnetic interactions not weak?”

“The color gauge theory postulates the existence of eight massless particles, sometimes called gluons, that are the carriers of the strong force just as the photon is the carrier of the electromagnetic force.”

“Strong, weak and electromagnetic interaction are evidently part of a grand unified theory. These temperatures are today quite inaccessible. They were achieved only in the earliest moments of the Big Bang. Since then, the universe has congealed, losing its symmetry.”