Back in 1900, physicists believed that they had discovered more or less all the laws governing the Universe.
The laws of classical mechanics (due to Newton), electromagnetism
(due to such men as Ampère, Gauss,
Faraday and Maxwell) and
thermodynamics (due to such men as Joule, Kelvin
and Boltzmann) seemed to explain pretty
much everything. Physicists thought that all they had to do was dot the i's and cross the t's.
Lord Kelvin said in 1900 to an assemblage of physicists at the British Association for the Advancement
of Science that "there is nothing new to be discovered in physics now. All that remains is more and more precise
However, at the beginning of the 20th century two new theories emerged that revolutionized the way physicists
looked at the Universe - Einstein's theory of special relativity and
quantum mechanics (due to men such as Bohr, de Broglie,
Heisenberg, Schrödinger and
Dirac). The unification of these theories led to the idea of antimatter.
This in turn led to the mystery of why the Universe contains more matter than antimatter. It is this mystery
that the BaBar experiment is investigating.