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Fermions and bosons are the two classes of elementary particles. Fermions are the particles that actually compose **matter** whereas bosons are associated with mediating the fundamental forces of nature between fermions. Fermions are particles whose quantum mechanical spin number is a half-integral (1/2, 3/2, 5/2, etc.) and obeys Fermi-Dirac statistics. In 1926 **Paul Dirac** and **Werner Heisenberg** applied the Pauli principle, which states that, the complete **wave function**, including both spatial and spin coordinates, of a system of identical fermions must be antisymmetric with respect to interchange of all of the coordinates of any two particles. This means that in a system of identical fermions each spin-orbit can hold no more than one fermion.

There are two classes of fermions, elementary fermions, such as leptons and **quarks**, and composite fermions, such as protons and neutrons. The leptons subclass is broken down into three groups or generations that each consist of one charged...

This section contains 728 words(approx. 3 pages at 300 words per page) |