Walter A. Simmons

Analysis of a six-quark model with right-handed currents☆

A model for the weak interactions using the six-quark model of Harari, right-handed currents, and heavy leptons which was proposed previously by some of us is analyzed in considerable detail. The model is one of a class of “vector-like” theories that are free of gauge theory anomalies. The neutral current is pure vector, which leads to predictions for diffractive production of vector mesons by neutrinos that are different from the predictions of the standard Weinberg-Salam model; the A1 uncouples and the fractions of ϱ and ω are enhanced. It is also predicted that relative production of I = 12 final states is larger than I = 32 final states in vN → vNπ in contrast to the Weinberg-Salam model. The non-leptonic decays of hyperons and mesons and the restrictions imposed by chiral symmetry are discussed. The decays of the charmed mesons are shown to be very rich due to the presence of both V − A and V + A interactions. The y-anomalies in neutrino interactions are discussed and calculations of dσdx and dσdy for both neutrinos and antineutrinos using modified Kuti-Weisskopf distributions are presented. Cross sections and ratios of neutrino and a neutrino cross sections are shown along with available experimental data. The v-distribution of dimuon events is also presented and compared with experiment. It is concluded that the model is not inconsistent with the currently available data.

Quark-number selection rule for nonleptonic weak decays

Recent experimental observations such as τ(D0)<τ(D+) were anticipated in a 1972 paper by Hayashi, Nakagawa, Nitto, and Ogawa, in which a quark-number selection rule for nonleptonic weak decays was proposed. We present here a diagrammatic interpretation of this selection rule and discuss several specific predictions and tests involving charmed mesons and baryons as well asb-flavored particles.

The Principle of Stationary Action in Biophysics: Stability in Protein Folding

We conceptualize protein folding as motion in a large dimensional dihedral angle space. We use Lagrangian mechanics and introduce an unspecified Lagrangian to study the motion. The fact that we have reliable folding leads us to conjecture the totality of paths forms caustics that can be recognized by the vanishing of the second variation of the action. There are two types of folding processes: stable against modest perturbations and unstable. We also conjecture that natural selection has picked out stable folds. More importantly, the presence of caustics leads naturally to the application of ideas from catastrophe theory and allows us to consider the question of stability for the folding process from that perspective. Powerful stability theorems from mathematics are then applicable to impose more order on the totality of motions. This leads to an immediate explanation for both the insensitivity of folding to solution perturbations and the fact that folding occurs using very little free energy. The theory of folding, based on the above conjectures, can also be used to explain the behavior of energy landscapes, the speed of folding similar to transition state theory, and the fact that random proteins do not fold.