By means of Regge theory and bootstraps, we motivate a chiral SU(2)⊗SU(2) noninvariance algebra of the meson isobar coupling strengths. We discuss the equivalence of these approaches and compare our algebra with the previously postulated algebras of the meson isobar system.

We explain $p-p$ differential scattering cross section at 90° and laboratory momentum 5-13.4 GeV/c in terms of two optical potentials and distorted-wave Born approximation of the corresponding amplitudes. The radial dependence of these potentials indicates two hadronic density distributions of the proton of root-mean-square radii 0.40 and 0.26 F.

We have scanned 550 000 pictures of stopping $K^{-}$ mesons in hydrogen for the decays ${\Sigma }^{\pm }\to \Lambda +e^{\pm }+\nu$, and find ${\Sigma }^{-}\to \Lambda +e^{-}+\nu /\mathrm{all}$ ${\Sigma }^{-}$ decays to be (0.64±0.12)×${10}^{-4\mathrm{}}$ and ${\Sigma }^{+}\to \Lambda +e^{+}\nu /\mathrm{all}$ ${\Sigma }^{+}$ decays to be (0.20±0.08)×${10}^{-4\mathrm{}}$. The rate for ${\Sigma }^{-}\to \Lambda +e^{-}+\nu$ yields a value of $D=0.76\mathrm{}\pm 0.07$, and $\alpha =\frac{D}{\mathrm{}(D+F)\mathrm{}}=0.64\mathrm{}\pm 0.06$. The observed electron-neutrino angular correlation together with the lambda polarization determines the magnitude of the ratio of vector to axial-vector coupling for this decay to be 0.31±0.30, consistent with the hypothesis of conserved vector current, with the absence of second-class currents, and with time-reversal invariance.

In a study of 9629 decays of ${K_L}^0$, the branching ratio [${K_L}^0\to {\pi }^{+}+{\pi }^{-}+\frac{{\pi }^0}{{K_L}^0}\to \mathrm{all}\mathrm{charged}\mathrm{modes}$] has been measured as 0.161 ± 0.005. These decays have been selected from the data with a background from the ${K_L}^0$ leptonic modes of approximately 17%, and the energy spectrum of the ${\pi }^0$ meson fitted to a decay matrix element of the form $M=1-\left(\frac{a_0}{{M_{\pi }}^2}\right)(S_3-S_0)$. The best fit value of the parameter $a_0$ was -0.249 ± 0.018.

A new type of superconvergent sum rules for $\pi -N$ scattering amplitudes has been derived and compared with the experiments.

A distinction is drawn between the divergence of the canonical commutator for composite fields and the condition $Z=0\mathrm{}$ for equivalence of an elementary field theory to a composite theory.

We describe a critical test of the pion-nucleon forward dispersion relations up to the highest energies practical at the Brookhaven alternating-gradient synchrotron involving a precise measurement of both the real and imaginary parts of the $\pi -N$ scattering amplitude. We find that the predictions of the $\pi -N$ forward dispersion relations are in good agreement with the experiment up to at least 20 BeV/c.

The secondary proton and pion spectra from proton-proton interactions have been measured over nearly the entire momentum range and over a wide range of laboratory angles. Most of the data are at an incident-proton momentum of 30 BeV/c.

The proton spectra were transformed into cross sections in terms of ${p_{\perp }}^{*}$ and ${p_{\parallel }}^{*}$ all in the c.m. system. These cross sections were found to be largely independent of ${p_{\parallel }}^{*}$ and an empirical fit was obtained quite similar to one derived by Hagedorn using a statistical model. The pion spectra were also expressed in terms of ${p_{\perp }}^{*}$ and ${p_{\parallel }}^{*}$ and found to be different from the proton spectra by showing a marked dependence on ${p_{\parallel }}^{*}$.

A phenomenological analysis of the proton spectra resulting from inelastic proton-proton interactions is presented which suggests the existence of a bremsstrahlung-type process of pion production for highly inelastic collisions. A relation $\overline{n}=\frac{{p_0}^{*}{sin\theta }^{*}}{0.4}$ is found between the implied average number of produced pions $\overline{n}$, the c.m. angle of scatter of the proton ${\theta }^{*}$, and the c.m. incident-proton momentum ${p_0}^{*}$. A simple expression for the differential cross section for secondary protons yields excellent agreement with data over a wide range of angle, momenta, and incident-proton momenta.

The nonleptonic decay amplitudes of the $K$ mesons are calculated using current algebra and the spectral-function sum rules. The result is convergent in the intermediate-boson model, but not for a direct current-current interaction. Comparison with the observed rate for ${K_1}^0$ decay shows that the intermediate-boson mass is about 8 BeV.

A model of two-dimensional hydrogen-bonded crystals satisfying the ice rule is presented and solved exactly in the presence of an external electric field. The transfer-matrix method is used. The model includes, for special values of the parameters, the ice problem, the Rys $F$ model of an antiferroelectric, and the Slater KDP model of a ferroelectric.

The Slater KDP model is solved for all temperatures and with an electric field. Above $T_c$ the specific heat behaves like ${(T-T_c)}^{-\frac{1}{2}}$ and the polarizability like ${(T-T_c)}^{-1\mathrm{}}$. There is a first-order phase transition at $T_c$ (latent heat). Below $T_c$ the free energy is simply $-\left|\mathcal{E}\right|d$ ($\mathcal{E}=\mathrm{electric}\mathrm{field}$, $d=\mathrm{dipole}\mathrm{moment}$).

The measured electrical conductivity of pure RbCl is separated into the usual anion and cation contributions with activation energies of 2.55 and 1.58 eV, respectively. By comparison with corresponding results for KCl and NaCl it is found that the alkali-chloride anion and cation activation energies differ most for nearly equal anion and cation radii. We conclude from this anomalous trend that an extension of conventional theory is required.

It has been found that the relation $\ln I\propto V^{\frac{1}{2}}$ accurately describes flux flow in superconductors in both the "linear" and "nonlinear" portions of the $I-V$ curves. The validity of this relation is sample independent.

We consider the possibility of superconductive pairing of two electrons separated by a barrier. We argue that such pairing is possible in principle for all metals and may lead to high transition temperatures.

Increases in the transition temperature of a structure consisting of alternate 60-Å layers of superconductor $S$ and barrier material $B$ are observed whenever the sequence $\mathrm{SBS}$ is formed. The effect was observed for Al, Zn, In, Sn, and Pb and for a variety of barrier materials.