Anti-Matter
At the Big Bang equal amounts of Matter and Anti-Matter were created. When they meet they destroy each other, but Anti-Matter decays faster.
The
matter we see in the universe today is just a tiny fraction of two vast seas of
matter and anti-matter. They would have completely destroyed one another
were it not for the tiny imbalance Joanne (Hewitt) and her colleagues found
between the B and Anti-B Mesons.