Why does our universe exist? If there was just as much antimatter as matter in our universe, it would annihilate without ever getting the chance to form stars, stars galaxies and our own planet Earth. You and everything you touch is made of matter. However, if you were to meet someone made of antimatter and shake their hand, the both of you would annihilate in a blinding flash of light.

Symmetry between matter and antimatter would prohibit the universe from expanding to the way we see it today. Since our universe obviously exists, there must be a break in the symmetry between matter and antimatter.  A break in symmetry is a very unusual experience in the universe. For example, it would be extremely odd to walk into a shoe store and find only right footed shoes. It might also be awkward to wake up in the morning and discover that none of your socks match. These are examples of asymmetry.

The 2008 Nobel Prize in Physics was awarded to Yoichuro Nambu, Makoto, Kobayashi, and Toshihide Maskawa for discovering broken symmetry in the universe. Nambu was the first to introduce spontaneous symmetry violations in particle physics. Koayashi and Maskawa used the concept of broken symmetry to predict the existence of three quarks: charm, bottom, and top. These quarks were later discovered in particle accelerator experiments.

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