Breaking the symmetry between fundamental forces
(PHYSorg.com Physics)

A fraction of a second after the Big Bang, a single unified force may have shattered. Scientists from the CDF and DZero Collaborations used data from the Fermilab Tevatron Collider to re-create the early universe conditions. They measured the weak mixing angle that controls the breaking of the unified force. Measuring this angle, a key parameter of the standard model, improves our understanding of the universe. The details of this symmetry breaking affect the nature of stars, atoms, and quarks. The new measurement of the weak mixing angle helps cement our understanding of the past, the character of what we observe today, and what we believe is in store for our future.