Degenerate energy levels

Energy level of a quantum system

In quantum mechanics, an energy level is degenerate if it corresponds to two or more different measurable states of a quantum system. Conversely, two or more different states of a quantum mechanical system are said to be degenerate if they give the same value of energy upon measurement. The maximum number of linearly independent states corresponding to a particular energy level is known as the degree of degeneracy (or simply the degeneracy) of the level.

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