학술논문

Reply to: ``Comment on: `Quantum action-angle variables for the harmonic oscillator'\,'' [Phys.\ Rev.\ Lett.\ {\bf 80} (1998), no. 12, 2745, MR1612279 (2000i:81022b)] by T. B.\ Smith and J. A.\ Vaccaro.
Document Type
Journal
Author
Lewis, H. Ralph (1-DTM-PA) AMS Author Profile; Lawrence, Walter E. (1-DTM-PA) AMS Author Profile; Harris, Joseph D. (1-DTM-PA) AMS Author Profile
Source
Physical Review Letters (Phys. Rev. Lett.) (19980101), 80, no.~12, 2746. ISSN: 0031-9007 (print).eISSN: 1079-7114.
Subject
81 Quantum theory -- 81Q General mathematical topics and methods in quantum theory
  81Q05 Closed and approximate solutions to the Schrödinger, Dirac, Klein-Gordon and other equations of quantum mechanics
Language
English
Abstract
\follows from CnoFile {1 612 279}{remarks} Summary of the first paper: ``Operators conjugate to the Hamiltonian are constructed explicitly for the quantum harmonic oscillator by two approaches in the space spanned by the eigenstates of $q$ and the eigenstates of $p$. The operators are quantum analogues of a classical angle variable divided by the oscillator frequency. Matrix elements are evaluated in the coherent state representation. Either conjugate operator can be used to construct an explicitly time-dependent operator invariant. It can be used as the starting point in a new perturbative procedure for constructing invariant operators for nonlinear, nonautonomous Hamiltonians.'' \par \{The comment by Smith and Vaccaro questions parts of the authors' arguments. They raise questions in regard to certain matrix elements of commutators and the use of the, in general multivalued, logarithm and arctangent functions in constructing the phase and time operators. The authors reply, defending their particular use of commutators and similarly the propriety of the use of the logarithm and arctangent in their particular context.\} \par \{For related, and in some respects more general, work see papers by C. M. Bender\ and G. V. Dunne\ [Phys. Rev. D (3) {\bf 40} (1989), no.~8, 2739--2742; MR1019516 (90m:81013); Phys. Rev. D (3) {\bf 40} (1989), no.~10, 3504--3511; MR1024743 (90k:81029)] and Bender [in {\it Lie algebras, cohomology, and new applications to quantum mechanics (Springfield, MO, 1992)}, 31--45, Contemp. Math., 160, Amer. Math. Soc., Providence, RI, 1994; MR1277373 (95e:81030)].\}