An axiomatization of the lattice of higher relative commutants of a subfactor

Summary We consider certain conditions for abstract lattices of commuting squares, that we prove are necessary and sufficient for them to arise as lattices of higher relative commutants of a subfactor. We call such lattices standard and use this axiomatization to prove that their sublattices are standard too. We consider a method for producing sublatties and deduce from this and [Po5]| some criteria for bipartite graphs to be graphs of subfactors.Oblatum 25-XI-1994Supported in part by NSF Grant DMS-9206984     

Relativistic nuclear physics at the Joint Institute for Nuclear Research

The basic stages of the development of the Veksler and Baldin Laboratory of High Energies, Joint Institute for Nuclear Research, in Dubna are described briefly. Some experiments on the investigation of cumulative particle production and the new direction of investigation of the processes of hadron-nuclear and nuclear-nuclear interaction in which the quark structure of nuclei can be manifested—relativistic nuclear physics—are considered. Basic methodical and experimental results obtained at the synchrophasotron and Nuclotron are presented, ideas produced in collaboration with theoreticians of the Bogoliubov Laboratory of Theoretical Physics are discussed. An overview of investigations in the field of relativistic nuclear physics planned at the Nuclotron is given.     

Stochastic resonance to control diffusive motion in chemistry

This paper reports on a novel procedure to tune the effective diffusion coefficient of a field-sensitive reactant in the presence of a periodic external field. We investigate the motion of two negatively charged azo dyes interacting with alpha-cyclodextrin (alpha-CD) upon action of a periodic square wave electrical field. We show that the dyes exhibit an effective diffusion coefficient D(eff) that depends on the rate constants for dye complexation within alpha-CD, the period and the amplitude of the field. UV-vis absorption, gradient field (1)H NMR, and fluorescence correlation spectroscopy (FCS) after two photon excitation are used to evidence that D(eff) may be increased far beyond its intrinsic value when specific relations interpreted as a stochastic resonance are fulfilled. The present results may find useful applications in chemical kinetics as well as for molecular sorting.     

Isolated photon cross section in p&pmacr; collisions at radicals = 1. 8 TeV

We report a new measurement of the cross section for the production of isolated photons with transverse energies ( E(gamma)(T)) above 10 GeV and pseudorapidities |eta|<2.5 in p&pmacr; collisions at sqrt[s] = 1.8 TeV. The results are based on a data sample of 107.6 pb(-1) recorded during 1992-1995 with the D0 detector at the Fermilab Tevatron collider. The background, predominantly from jets which fragment to neutral mesons, was estimated using the longitudinal shower shape of photon candidates in the calorimeter. The measured cross section is in good agreement with the next-to-leading order QCD calculation for E(gamma)(T) greater, similar36 GeV.     

Almost Automorphic Functions in Frechet Spaces and Applications to Differential Equations

In this paper we first develop a theory of almost automorphic functions with values in Frechet spaces. Then, we consider the semilinear differential equation x'(t) = A x(t) + f(t, x(t)), t ∈ ℝ in a Frechet space X, where A is the infinitesimal generator of a C₀-semigroup satisfying some conditions of exponential stability. Under suitable conditions on f, we prove the existence and uniqueness of an almost automorphic mild solution to the equation.     

Supercurrent anomaly in non-abelian supersymmetric theories

A method for regularizing the supercurrent, preserving both gauge invariance and supersymmetry is developed, using point-splitting regularization and path-dependent phase factors in superspace. The supercurrent anomaly for general non-abelian supersymmetric theories is obtained on the mass-shell in the one-loop approximation.     

EPR study of the structure of mechanically activated periclase powders

The EPR method has been used to study mechanically activated periclase powders. The Mn²⁺ and Cr³⁺ spectra in MgO depend on the number of defects. The lines broaden to a degree which depends on the nuclear spin; the ratio between the hyperfine components changes; the line shape changes from Lorentzian to a convoluted form; and the relative intensity of the forbidden transitions in the Mn²⁺ changes.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, Vol. 12, No. 3, pp. 48–52, March, 1969.     

Synthesis and Stereochemistry of Some New 1,3-Oxathiane Derivatives

Summary. The synthesis and stereochemistry of some new 2,5-substituted 1,3-oxathiane derivatives are reported. The anancomeric or flexible structure of the derivatives and some peculiar cases of prochirality are revealed by NMR investigations.