Definition: Fincins is a term used in the field of biophysics and quantum mechanics, specifically referring to the concept of Fock states, which are a class of mathematical objects that generalize the Hilbert space of wave functions. In quantum mechanics, Fock states represent the probability distributions over all possible states of a quantum system. They can be thought of as a set of "finitely many" states that describe the state of the entire quantum system at once. These states are often used to model