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Standard Model

The "Standard Model" refers to the current model physicists have for the structure of the universe. This model makes use of two types of particles for accounting for all the objects seen in the universe. These two types of particles are called LEPTONS and QUARKS. This model goes on to say that there are three families of both leptons and quarks, with each family consisting of two particles; thus, there are a total of six leptons and six quarks. Keep in mind that each of these particles also has an antiparticle sister, so really there are a total of 12 leptons and another 12 quarks.

The standard model explains and gives rules as to how leptons and quarks interact with each other to build the hundreds of particles that can exist in nature. Many of the rules are determined by the properties and behaviors of the GAUGE BOSONS, which are other particles that are responsible for the fundamental forces we see in nature. The standard model includes three of the four known forces of nature: the strong nuclear, weak nuclear and electromagnetic forces. The gauge bosons include the gluon, W and Z bosons, and the photon. Keep in mind that the idea of particles "creating" forces originally comes from quantum theory, which was formulated in the early part of the twentieth century to explain electromagnetic interactions. Physicists now believe that all forces must be the result of the exchange of particles (a fancier way of saying this is that the "fields are quantized").

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