Carrier of force

We can siunmarize all of the above research carried out over the last two centuries in that a photon is a qucuitum of radiation and a carrier of force between particles, whereas an electron is a quantum of matter. Now, let us examine the more mundane aspects of light measurement including color measurement. 

Scientists have long doubted that all the particles produced with masses between the electron and the proton (loosely referred to as mesons, i.e. "intermediate"), and with masses greater than the proton (referred to as baryons, "heavy") really are "elementary . It was proposed that they have a substructure or constitute excited states of each other. Are they waves or particles since they serve as carriers of force. At this point it is important to understand what is meant by "particle" in nuclear physics. 

Fermions are the building blocks of nature. There is another group of "particles" called bosons, to which the photon and mesons belong. The bosons are the carriers of forces. When two fermions interact they continually emit and absorb bosons. The bosons have an even spin (0, 1, etc), they do not obey the Pauli principle, and they do not require the formation of anti-particles in their reactions. 

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