Showing papers in "Physics Letters A in 1984"

TL;DR: In this paper, randomly oriented "nanocrystal" with sizes d below 10 nm, were compacted into a nanocrystalline solid, which consists of crystalline domains and a connective matrix without any short or long range order.

TL;DR: In this paper, a nonlinear Schrodinger equation with a self-interacting term was proposed and the separability conditions of Bialynicki-Birula were satisfied in an asymptotic sense.

TL;DR: In this article, a super-extension of the Korteweg-de Vries equations and modified versions of the Miura transformation is proposed, and the integrability of the hierarchies of these new supersystems is proved.

TL;DR: In this paper, a nonlinear evolution equation for one dependent variable in two spatial dimensions integrable by the inverse scattering transform method is presented, which is a special case of the one in this paper.

TL;DR: The crystal structures of Si and Ge were studied by energy dispersive X-ray diffraction at room temperature and pressures up to 50 GPa as mentioned in this paper, showing that Si transforms to a primitive hexagonal (Si-V) structure around 16 GPa, to an intermediate phase Si-VI between 35 and 40 GPa.

TL;DR: In this paper, a class of approximation of the two-particle density matrix d2 resembling the Hartree-Fock dependence on the one particle density matrices d1 is suggested.

TL;DR: In this article, an algorithm for constructing a chain of quantum hamiltonians with interconnected energy spectra is proposed for an arbitrary number of space dimensions, and the supersymmetric nature of the relation between connected quantum systems is pointed out.

TL;DR: In this article, the concept of hamiltonian sysem was generalized to include a wide class of dissipative processes, such as particle collisions, three-wave interactions, and wave-particle resonances.

TL;DR: In this paper, a bracket formulation for irreversible fields analogous to that for hamiltonian fields is presented, which contains a bracket with symmetric and antisymmetric components and a generator of time translation.

TL;DR: An explicit determinant formula for the N-fols Backlund transform of any pair of AKNS fields q(x, t), r(x and t) is derived in this paper.

TL;DR: In this paper, the authors show that remerging Feigenbaum trees are quite common in models with more than one parameter and discuss a number of criteria under which they are generally observed.

TL;DR: In this article, the bracket formulation of the Euler fluid mechanics equations is extended to the fluid mechanics equation corresponding to the Navier-Stokes-Fourier and the Edelen constitutive relations.

TL;DR: In this paper, a new class of exact inhomogeneous solutions to Einstein's equations with non-zero cosmological constant and zero pressure was given, which generalize the de Sitter space-time and evolve towards a state that is stationary inside the event horizon of any future inextendible time-like curve and confirm the cosmic no hair conjecture.

TL;DR: D disorder and entropy are formally decoupled in such a way that it is possible for an expanding universe to have periods in which both entropy and order increase simultaneously.

TL;DR: In this article, the spectrum of an incommensurate electron system is studied through a dynamical map and the imbedded horseshoe structure in the map leads to the infinite hierarchical structure of the energy spectrum.

TL;DR: In this article, an integrable model describing the interaction of spin-S impurities with an isotropic Heisenberg chain is presented, which is diagonalized and its thermodynamics formulated.

TL;DR: In this paper, a non-local linear integral equation is studied, which allows for Backlund transformations in the measure, and the compatibility of three of these transformations leads to an integrable nonlinear three-dimensional lattice equation.

TL;DR: In this paper, the crystal structures of Mg, Ca, Sr and Ba were studied by energy dispersive X-ray diffraction at room temperature and pressures up to 35, 42, 46 and 40 GPa respectively.

TL;DR: In this paper, the entropic uncertainty relations for angle-angular momentum and position-momentum were derived, which are related to older relations of a similar type, which were proved by Bialynicki-Birula and Mycielski.

TL;DR: In this paper, it was shown that the self-dual gauge field equations satisfy the Painleve property for any gauge group, for any group, and that they are solvable.

TL;DR: In this article, the authors derived analytic expressions for characteristic functions, moments, and moment functions of chaotic maps in the form of Chebyshev polynomials and derived higher-order moment functions, which are important for a characterization of non-gaussian processes exhibited by many chaotic maps.

TL;DR: In this paper, statistical properties of acoustic emissions from a human ear are measured and compared with the theory of quantum-limited oscillations, both in qualitative and quantitative features, strongly supporting previous theoretical arguments for the importance of quantum noise in the inner ear.

TL;DR: In this paper, the modes of oscillation of a Schwarzschild black hole were determined within an analytic framework, and the quasi-normal modes were related to the bound states of the inverted black hole potential which was approximated by the inverted Eckart potential.

TL;DR: In this article, the possibilities for flourescence detection of surface EXAFS are studied using thin films of gold on various substrates, and it is found that excellent signal to noise ratios can be obtained even for submonolayer films, demonstrating that the technique should have wide applicability to surface and near surface systems.

TL;DR: In this article, a mean field theory for fractal dimensions of diffusion-limited aggregates grown on a substrate surface of arbitrary dimensionality is proposed and the results are in good agreement with those of the computer simulations for all dimensions.

TL;DR: In this article, the ground state energy and spin wave modes for an anisotropic Heisenberg chain of arbitrary spin were obtained for the Ising-like anisotropy, while for the XY -like case there was no gap.

TL;DR: In this article, the authors demonstrated that neutron absorption in one of the two beam paths of a neutron interferometer gives different interference patterns with static and with time-dependent absorption even when the time-averaged absorption is the same.

TL;DR: In this article, the scaling hypothesis for localization of 2D-electrons in a magnetic field B was studied and it was shown that at T = 0 conductivity σxx has maxima.

TL;DR: In this article, it was demonstrated that plane wave solutions of linearized conformal gravity propagate six physical degrees of freedom, corresponding to massless spin-2 and spin-1 ordibary particles and a massless Spin-2 ghost particle.

TL;DR: The quantum theory of the two-level atom coupled to a single mode of the electromagnetic field is considered as a simple example of "quantum chaos" defined as the quantum behavior of a dynamical system which is non-integrable in the classical limit.