The particle family structure

At the lowest level so far discovered there are twelve kinds of matter particles: six quarks and six leptons.
    The matter particles come in three "families". Each family consists of two quarks and two leptons. In addition to the matter particles there are other particles, force particles. These are responsible for three of our known forces - strong, electromagnetic and weak. Only the force of gravity falls outside their sphere of influence. The essential difference between quarks and leptons is that leptons are not affected by the strong force. The families, on the other hand, behave very much like copies of each other.



Man seeks answers about his home, the Universe, which was created in the Big Bang some 15,000 million years ago. What does it consist of? What are its smallest building blocks and what are their properties? What can they tell us of the history of the Universe and its future?
    This year's Nobel Laureates, through the discovery of the tau and the neutrino, have increased our knowledge of the cosmos.


For its first instant the Universe was a hot soup of subatomic particles, including quarks and leptons. These were what determined the later development of the Universe, including the division between matter and antimatter.

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