Question

What direct evidence do we have that the weak and electromagnetic forces were once unified as a single electroweak force?

A) The most advanced telescopes are able to see back to this era in the universe.
B) Detectors on Earth have received photons and high-energy particles from this era.
C) Temperatures in the center of the Sun can reproduce the conditions during this era.
D) Particle accelerators on Earth can reach energies equivalent to the high temperatures of this era and have produced particles predicted by the electroweak theory.
E) We have no direct evidence of the electroweak force

Answer 1

The direct evidence for the unification of the weak and electromagnetic forces as a single electroweak force comes from studying the expansion of the universe and the conditions shortly after the Big Bang.

Step-by-step explanation:

From looking increasingly inward at smaller details for direct evidence of electroweak theory and GUTS, we turn around and look to the universe for evidence of the unification of forces. In the 1920s, the expansion of the universe was discovered. Thinking backward in time, the universe must once have been very small, dense, and extremely hot. At a tiny fraction of a second after the fabled Big Bang, forces would have been unified and may have left their fingerprint on the existing universe. This, one of the most exciting forefronts of physics, is the subject of Frontiers of Physics.