Analytic Representations of Finite Quantum Systems on a Torus

Muna Jabuni

Published Jan 1, 2010• 0 citations

Abstract

Quantum systems with a finite Hilbert space, where position x and momen- \ntum p take values in Z(d) (integers modulo d), are studied. An analytic \nrepresentation of finite quantum systems is considered. Quantum states are \nrepresented by analytic functions on a torus. This function has exactly d \nzeros, which define uniquely the quantum state. The analytic function of a \nstate can be constructed using its zeros. As the system evolves in time, the \nd zeros follow d paths on the torus. Examples of the paths ³n(t) of the zeros, \nfor various Hamiltonians, are given. In addition, for given paths ³n(t) of the \nd zeros, the Hamiltonian is calculated. Furthermore, periodic finite quantum \nsystems are considered. Special cases where M of the zeros follow the same \npath are also studied, and general ideas are demonstrated with several ex- \namples. Examples of the path with multiplicity M = 1; 2; 3; 4; 5 are given. It \nis evidenced within the study that a small perturbation of the initial values \nof the zeros splits a path with multiplicity M into M different paths.

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