A Hamiltonian formulation of the Pais-Uhlenbeck oscillator that yields a stable and unitary quantum system

作者：Mostafazadeh Ali^*

来源：Physics Letters, Section A: General, Atomic and Solid State Physics , 2010, 375(2): 93-98.

DOI：10.1016/j.physleta.2010.10.050

• Higher derivative theories
• Unitarity
• Stable quantum system
• PT-symmetry
• Pseudo-Hermiticity

We offer a new Hamiltonian formulation of the classical Pais-Uhlenbeck oscillator and consider its canonical quantization. We show that for the non-degenerate case where the frequencies differ, the quantum Hamiltonian operator is a Hermitian operator with a positive spectrum, i.e., the quantum system is both stable and unitary. Furthermore it yields the classical Pais-Uhlenbeck oscillator in the classical limit. A consistent description of the degenerate case based on a Hamiltonian that is quadratic in momenta requires its analytic continuation into a complex Hamiltonian system possessing a generalized PT-symmetry (an involutive antilinear symmetry). We devise a real description of this complex system, derive an integral of motion for it, and explore its quantization.

• 出版日期2010-12-1