Factorization in finite quantum systems
Apostol Vourdas · Journal of Physics A Mathematical and General · 2003
Unitary transformations in an angular momentum Hilbert space H (2 j + 1), are considered. They are expressed as a finite sum of the displacement operators (which play the role of SU (2 j + 1) generators) with the Weyl function as coefficients. The Chinese remainder theorem is used to factorize large qudits in the Hilbert space H (2 j + 1) in terms of smaller qudits in Hilbert spaces H (2 j i + 1). All unitary transformations on large qudits can be performed through appropriate unitary transformations on the smaller qudits.