Sometimes, there is an absolute limit on the number of terms an officeholder can serve, while, in other cases, the restrictions are merely on the number of consecutive terms.
For example, Maxwell's Equations would always be capitalized, while quantum mechanics is usually un-capitalized. I searched half a dozen sites for an answer to this but found no clue about a rule. So go either way that makes you happy, but (most of all) be consistent.
quantum state. n. (Atomic Physics) physics a state of a system characterized by a set of quantum numbers and represented by an eigenfunction. The energy of each state is precise within the limits imposed by the uncertainty principle but may be changed by applying a field of force. States that have the same energy are called degenerate.