We report observations of long-lived persistent currents in both the $A$ and $B$ phases of ${}_{}{}^3{}_{}{}^{}\mathrm{He}$. In this work we have exploited the relation between the dissipation of small-amplitude oscillatory superflow and the average relative velocity between the superfluid and normal-fluid components. This provides a new technique for the nondestructive determination of the superfluid velocity associated with persistent currents in liquid ${}_{}{}^3{}_{}{}^{}\mathrm{He}$.

The rotational diffusion constant $D_r$ of entangled rodlike polymers in semidilute solution was calculated by our refining quantitatively the Doi-Edwards tube model. The methods of probability and stochastic process theory were used to calculate the mean lifetime of tubes, while the mean step angle of jump diffusion was evaluated by computer simulation on the size distribution of tubes. Our result eliminates a large discrepancy of $D_r$ between the Doi-Edwards theory and a variety of experiments on rodlike polymers.

We observe a spontaneous electron-spin polarization in GaAs(110) in photoemission experiments using excitation with linearly polarized light. This effect is a consequence of the noncentrosymmetric crystal structure of GaAs and suggests that the polarization of each spin-split conduction band can be almost as high as ± 100%. A net nonzero polarization after summation over spin states arises from (a) differences in spin-up and -down conduction-band hybridization with valence $p$ states, and (b) surface-transmission effects.

We have determined the ESR properties of U${\mathrm{Be}}_{13}$ doped with dilute local moments of Er, Dy, or Gd over the temperature region where there is a large variation in the enhanced specific heat. We find that neither the enhancement, the temperature variation, nor any other anomalous behavior appears to be mirrored in the ESR data. We suggest that this unexpected result must be incorporated into current models of heavy-fermion systems.

The contrasting equilibrium and transport experimental results in the solids which exhibit heavy-fermion behavior are used to specify a phenomenological theory which puts strong constraints on a microscopic description. These constraints are not satisfied by a Fermi-liquid theory similar to that for liquid ${}_{}{}^3{}_{}{}^{}\mathrm{He}$. The heavy mass arises through the renormalization of conduction electrons by the exchange of spin fluctuations of what at high temperatures were the local moments. Expressions for the specific-heat and the magnetic-susceptibility enhancements in terms of the Landau interaction functional and predictions for some transport properties are given.

The intermetallic compound U${\mathrm{Ru}}_2$${\mathrm{Si}}_2$ can be classified as a heavy-fermion system because of its large linear specific-heat coefficient $\gamma =180\mathrm{}$ mJ/mol·${\mathrm{K}}^2$. Susceptibility, magnetization, and specific-heat measurements on single-crystal samples indicate both a magnetic phase transition at 17.5 K and a superconducting transition at 0.8 K. The magnetic and superconducting properties are highly anisotropic.

The authors have used NMR to determine the structure of surface species after the C-C bond scission of adsorbed acetylene and ethylene on Pt clusters produced by heating the samples to 690 K. They have found the species to be predominantly isolated carbon atoms adsorbed on Pt surfaces. They have studied the mobility of adsorbed carbon atoms from motional narrowing of the ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ line shapes and motion-induced shortening of the spin-lattice relaxation times. They have found that the carbon atoms on Pt clusters are very mobile, their activation energy of 7 ± 1 kcal/mole for translational motion being less than half of CO on Pt clusters.

Cosmic-ray spectra are calculated within the fully nonlinear theory of shock acceleration including the finite phase velocity of the scattering Alfvén waves. The spectra are weakly dependent on shock parameters over the range typical of supernova remnants, and in good agreement with the observations. Nevertheless, the very hard spectra indicated by ultrahigh-energy observations of compact binary sources can be accounted for with extremely strong shocks.

By means of the quantum-potential interpretation we show that there is no need for a break or "cut" in the way we regard reality between quantum and classical levels.

We study a class of local probabilistic growth processes that includes the kinetic-growth algorithm for generating percolation clusters. The shapes of the growing clusters are controlled by $p$, the probability of growth. For $p>\mathrm{}{p}_c$, the shapes are scale invariant with time and show interesting morphological features including both smoothly curved sections and straight facets. The facets are shown to be related to the problem of directed percolation and disappear below the directed-percolation threshold. A simple random-walk model for computing the shapes of our clusters is described.

It is shown that a straightforward version of a classical Kaluza-Klein theory predicts the existence of classical vacuum polarization and that if the $g_{55}$ field carries a mass than the theory admits centrally symmetric solutions for which the Schwarzschild singularity becomes a naked point singularity with no event horizon and for which the electric field is everywhere finite.

The traditional version of the JWKB connection formula at a linear turning point is incorrect. The correct version follows from the Borel-based summability of the Airy-function asymptotic expansions. A key point is that the classically forbidden region lies on a Stokes line. The real exponentially growing solution has an explicitly complex JWKB expansion, while the explicitly real exponentially growing JWKB expansion represents a complex solution. Inconsistencies in applications of the traditional formula, such as in transmission through a barrier, are eliminated.

The necessary and sufficient conditions under which fully probabilistic cellular-automata (PCA) rules possess an underlying Hamiltonian (i.e., are "reversible") are established. It is argued that, even for irreversible rules, continuous ferromagnetic transitions in PCA with "up-down" symmetry belong in the universality class of kinetic Ising models. The nonstationary (e.g., periodic) states achieved for asymptotically large times by certain PCA rules in the (mean field) limit of infinite dimension are argued to persist in two and three dimensions, where fluctuations are strong.

We discuss several experimental consequences of a lattice-gauge-theory calculation of the first two moments of the $\pi$ and $\rho$ distribution amplitudes. The second moments for both mesons are considerably larger than the values obtained from QCD sum-rule techniques. We show the qualitative difference that this makes in the predicted distribution amplitude, and demonstrate the consequences for the pion form factor and the $\gamma \gamma \to {\pi }^0{\pi }^0$ cross section.

Relative yields of $\phi$ and charged $K$ mesons are measured as functions of charged multiplicity in the central rapidity region for $\mathrm{pp}$, $\mathrm{dd}$, $p\alpha$, and $\alpha \alpha$ collisions at $\sqrt{s_{\mathrm{NN}}}=3.15\mathrm{} \mathrm{and} 44$ GeV. No anomalous strange-particle production is observed in $\alpha \alpha$ reactions relative to $\mathrm{pp}$ even at large multiplicities corresponding to events comprising less than 3.6×${10}^{-4\mathrm{}}$ of the inclusive cross section.

We have used standard numerical techniques of lattice quantum chromodynamics to look for evidence of the proposed doubly strange spin-zero dibaryon (the $H$ particle), and to determine the splitting between the mass of the $H$ and the mass of two $\Lambda \text{'}\mathrm{s}$, its lightest possible strong-decay channel. We find that the dibaryon is above the two-$\Lambda$ threshold, making it unstable to strong decay.

We have searched for the production of like-sign dilepton events (${\nu }_{\mu }+\mathrm{Ne}\to {\mu }^{-}+e^{-}+\dots$) in a wide-band neutrino beam at Fermilab using the 15-ft bubble chamber. We observe no signal above the background arising from conventional sources. We set 90%-confidence-level upper limits for the production rates of $\frac{({\nu }_{\mu }+\mathrm{Ne}\to {\mu }^{-}+e^{-}+\dots )}{({\nu }_{\mu }+\mathrm{Ne}\to {\mu }^{-}+\dots )}<~0.76\times {10}^{-4\mathrm{}}$ and $\frac{({\nu }_{\mu }+\mathrm{Ne}\to {\mu }^{-}+e^{-}+\dots )}{({\nu }_{\mu }+\mathrm{Ne}\to {\mu }^{-}+e^{+}+\dots )}<~5.3\times {10}^{-2\mathrm{}}$.

We show that the entire tree-level contribution to the low-energy effective action of a Calabi-Yau superstring compatification can be computed topologically in the field-theory limit.

We have measured the production polarization of 265- and 310-GeV/c ${\Sigma }^{-}$ in the inclusive reaction $p+\mathrm{Cu}\to {\Sigma }^{-}+X$ using 400-GeV/c protons. The polarization was analyzed via the asymmetry in the weak decay ${\Sigma }^{-}\to n+{\pi }^{-}$, and has typical values of +0.20 with respect to the direction of the cross product of the incident-proton and ${\Sigma }^{-}$ momenta. Using the spin-precession technique, we have determined the ${\Sigma }^{-}$ magnetic moment to be -1.23±0.03±0.03 nuclear magnetons, where the statistical and systematic errors are shown separately.

We make some quark-model and current-algebra estimates of the cross sections for an SU(5) monopole to catalyze proton decay into the channels $e^{+}{\pi }^0$ and $e^{+}+\mathrm{nonstrange}\mathrm{mesons}$.