Showing papers in "Annals of Physics in 1989"

TL;DR: It is shown that if one can find N + 1 mutually unbiased bases for a complex vector space of N dimensions, then the measurements corresponding to these bases provide an optimal means of determining the density matrix of an ensemble of systems having N orthogonal states.

TL;DR: In this article, a general framework for introducing nonlinear corrections into ordinary quantum mechanics, that can serve as a guide to experiments that would be sensitive to such corrections, is presented, including the precession of spinning particles in external fields, experiments of Stern-Gerlach type, and the broadening and de-tuning of absorption lines.

TL;DR: In this paper, it was shown that the non-integrable phase factor P exp(ig ∫ A μ dx μ }, a pathordered line integral along a non-contractable loop, becomes a dynamical degree of freedom in gauge theory.

TL;DR: In this article, a classical Poincare invariant particle dynamics is formulated in the framework of constraint Hamiltonian systems, which is compatible with physical requirements like world line invariance, cluster separability, causality principles, and a reasonable non-relativistic limit.

TL;DR: In this paper, a new form of equations of motion is proposed for d = 4 massless fields of all spins interacting with gravity, which are described in terms of a free differential algebra constructed from 1-forms and 0-forms belonging both to the adjoint representation of the superalgebra of higher-spin and auxiliary fields.

TL;DR: The phase-space approach to spin is developed from two basic principles, SU(2)-covariance and traciality, as a theory of Wigner functions on the sphere.

TL;DR: In this article, the authors extend the formal analysis of Baym and Kadanoff in order to derive the simplest self-consistent approximation based on exchange of fluctuations in the particle-hole and particle-particle channels.

TL;DR: In this article, a fully nonpolynomial framework for closed string field theory is studied, where all interactions are geometrical, the pattern of string overlaps gives polyhedra with equal perimeter faces and three edges at each vertex.

TL;DR: In this paper, a quantum analogue of the Baker's transformation is constructed using a specially developed quantization procedure, and a unitary operator acting on an N-dimensional Hilbert space, with N finite (and even), has similar properties to the classical baker's map, and reduces to it in the classical limit, which corresponds here to N → ∞.

TL;DR: In this paper, a variational approach to the one band Hubbard model in the limit of a large on-site Coulomb repulsion is presented and discussed, and the results obtained by numerical evaluation of the projected wavefunction are reviewed.

TL;DR: In this paper, the authors quantize the Chern-Simons theory in the functional Schrodinger representation and show how to solve the Gauss law constraint in the non-Abelian theory.

TL;DR: Theoretical analysis of the uses of lepton and nuclear polarization degrees of freedom in the extraction of information on nuclear structure and dynamics from exclusive electron-nucleus scattering is presented in this article.

TL;DR: In this paper, the modulus squared of the inner product of two state vectors is shown to be an eigenvalue of the operator representing a frequency measurement on the system of an infinite number of copies of the original system.

TL;DR: In this paper, the expectation of products of Wilson loops is evaluated using the stochastic differential calculus and a method of Bralic, and Euclidean invariance of the theory is proven.

TL;DR: In this article, the authors investigated the different possible ways of defining the semiclassical limit of quantum general relativity and developed rules for finding the back-reaction of the quantum mode q on the classical mode Q, which can be found using the phase of the wave function which describes the dynamics of q.

TL;DR: A few months ago I was asked to speak at a fest honoring my father and I had also been invited to visit Germany for 2 months as mentioned in this paper, and the first thing I did in preparation for my trip was to buy a good English-German dictionary.

TL;DR: In this article, the potential group SO(2, 2) was used to realize a class of solvable potentials and the scattering matrices can be obtained by purely algebraic techniques.

TL;DR: In this article, the authors apply the results of their recent investigation of integrable models to the particular case of the Toda lattice and obtain the conserved quantities in closed form and derive the recursion relation which leads to their involution.

TL;DR: In this article, the authors evaluated the coherent state path integral developed by Klauder for a chaotic system (the kicked rotator) and found that it provides an accurate time evolution of a wave function over a finite time period even for the chaotic system.

TL;DR: In this paper, the spectral deformation of the Vlasov operator L (θ) was used to derive a family of operators which depend analytically on the complex parameter θ.

TL;DR: In this article, the symmetry group of the three-wave resonant interaction system in three or more dimensions is shown to have the structure of the direct sum of three Kac-Moody-Virasoro u (1) algebras.

TL;DR: In this article, the authors derived the gravitational multiplets of new minimal Poincare supergravity and obtained a tensor calculus which allows us to compute general matter couplings in arbitrary R-symmetric supergravity theories.

TL;DR: In this paper, a method of acceleration of the convergence of the hyperspherical harmonic expansion, which allows very accurate direct solution of nonrelativistic three body equations, is presented.

TL;DR: In this article, a mechanism for several unexpected particle production phenomena observed recently in high energy collisions and characterized by very low transverse momenta or intermittency-type fluctuations in longitudinal rapidity is proposed.

TL;DR: In this paper, the space-times generated by 1-dimensional open and closed distributions of energy and tension in (2 + 1)-dimensional gravity were analyzed and the global structures of these geometries, which are locally flat outside the sources, were described.

TL;DR: In this article, the semiclassical theory for heavy-ion collisions in a complex, optical potential is studied on the basis of the complex Wentzel-Kramers-Brillouin approximation.

TL;DR: In this article, it was shown that the Schrodinger equation has solutions with asymptotic expansions of the form e − ∫ 0 1 E j (r) dr ϵ (φ j (t)+v 1 (ϵ)ζ j 1 (t,ϵ)+v 2 ζ j 2(t, ϵ)+…) (j=A,B) where they are equal.

TL;DR: In this article, a large family of new L-state cyclic solid-on-solid (CSOS) lattice models, related to the 8-vertex SOS and Andrews-Baxter-Forrester SOS models, is solved exactly.

TL;DR: In this article, a new class of exact solutions of Deser, Jackiw, and Templeton's theory (DJT) of topologically massive gravity which consists of homogeneous, anisotropic manifolds is presented.

TL;DR: In this paper, the computation of the operator algebra in conformal field theories with Feigin-Fuks type correlation functions is described, and the special features of non-diagonal theories are pointed out.