Inverse scattering and solitons in An−1A_{n-1} affine Toda field theories II

New single soliton solutions to the affine Toda field theories are constructed, exhibiting previously unobserved topological charges. This goes some of the way in filling the weights of the fundamental representations, but nevertheless holes in the representations remain. We use the group doublecross product form of the inverse scattering method, and restrict ourselves to the rank one solutions.Comment: 19 pages, latex, 12 fig

Flipped Angles and Phases: A Systematic Study

We discuss systematically the fermion mass and mixing matrices in a generic \linebreak field-theoretical flipped $SU(5)$ model, with particular applications to neutrino and baryon number-changing physics. We demonstrate that the different quark flavour branching ratios in proton decay are related to the Cabibbo-Kobayashi-Maskawa angles, whereas the lepton flavour branching ratios are undetermined. The light neutrino mixing angles observable via oscillation effects are related to the heavy conjugate (right-handed) neutrino mass matrix, which also plays a key role in cosmological baryogenesis. The ratios of neutrino and charged lepton decay modes in baryon decay may also be related to neutrino oscillation parameters. Plausible Ans\"atze for the generation structure of coupling matrices motivate additional relations between physical observables, and yield a satisfactory baryon asymmetry.Comment: 13 pages, no figures, latex (twice), CERN-TH.6842/93, UMN-TH-1130/93, CTP-TAMU-11/9

Inverse scattering and solitons in An−1A_{n-1} affine Toda field theories

We implement the inverse scattering method in the case of the $A_n$ affine Toda field theories, by studying the space-time evolution of simple poles in the underlying loop group. We find the known single soliton solutions, as well as additional solutions with non-linear modes of oscillation around the standard solution, by studying the particularly simple case where the residue at the pole is a rank one projection. We show that these solutions with extra modes have the same mass and topological charges as the standard solutions, so we do not shed any light on the missing topological charge problem in these models. We also show that the integrated energy-momentum density can be calculated from the central extension of the loop group.Comment: 28 pages, Latex, 4 figs include

Chaotic dynamics of superconductor vortices in the plastic phase

We present numerical simulation results of driven vortex lattices in presence of random disorder at zero temperature. We show that the plastic dynamics is readily understood in the framework of chaos theory. Intermittency "routes to chaos" have been clearly identified, and positive Lyapunov exponents and broad-band noise, both characteristic of chaos, are found to coincide with the differential resistance peak. Furthermore, the fractal dimension of the strange attractor reveals that the chaotic dynamics of vortices is low-dimensional.Comment: 5 pages, 3 figures Accepted for publication in Physical Review Letter

Driven flux-line lattices in the presence of weak random columnar disorder: Finite-temperature behavior and dynamical melting of moving Bose glass

We use 3D numerical simulations to explore the phase diagram of driven flux line lattices in presence of weak random columnar disorder at finite temperature and high driving force. We show that the moving Bose glass phase exists in a large range of temperature, up to its melting into a moving vortex liquid. It is also remarkably stable upon increasing velocity : the dynamical transition to the correlated moving glass expected at a critical velocity is not found at any velocity accessible to our simulations. Furthermore, we show the existence of an effective static tin roof pinning potential in the direction transverse to motion, which originates from both the transverse periodicity of the moving lattice and the localization effect due to correlated disorder. Using a simple model of a single elastic line in such a periodic potential, we obtain a good description of the transverse field penetration at surfaces as a function of thickness in the moving Bose glass phase.Comment: 5 pages, 4 figures, New title and minor changes in text and figures. Accepted for publication in Physical Review

Large Scale Baryon Isocurvature Inhomogeneities

Big bang nucleosynthesis constraints on baryon isocurvature perturbations are determined. A simple model ignoring the effects of the scale of the perturbations is first reviewed. This model is then extended to test the claim that large amplitude perturbations will collapse, forming compact objects and preventing their baryons from contributing to the observed baryon density. It is found that baryon isocurvature perturbations are constrained to provide only a slight increase in the density of baryons in the universe over the standard homogeneous model. In particular it is found that models which rely on power laws and the random phase approximation for the power spectrum are incompatible with big bang nucleosynthesis unless an {\em ad hoc}, small scale cutoff is included.Comment: 11pages + 8figures, LaTeX (2.09), postscript figures available via anonymous ftp from oddjob.uchicago.edu:/ftp/ibbn/fig?.ps where ?=1-8 or via email from [email protected], Fermilab-Pub-94/???-A and UMN-TH-1307/9

Exploration of the MSSM with Non-Universal Higgs Masses

We explore the parameter space of the minimal supersymmetric extension of the Standard Model (MSSM), allowing the soft supersymmetry-breaking masses of the Higgs multiplets, m_{1,2}, to be non-universal (NUHM). Compared with the constrained MSSM (CMSSM) in which m_{1,2} are required to be equal to the soft supersymmetry-breaking masses m_0 of the squark and slepton masses, the Higgs mixing parameter mu and the pseudoscalar Higgs mass m_A, which are calculated in the CMSSM, are free in the NUHM model. We incorporate accelerator and dark matter constraints in determining allowed regions of the (mu, m_A), (mu, M_2) and (m_{1/2}, m_0) planes for selected choices of the other NUHM parameters. In the examples studied, we find that the LSP mass cannot be reduced far below its limit in the CMSSM, whereas m_A may be as small as allowed by LEP for large tan \beta. We present in Appendices details of the calculations of neutralino-slepton, chargino-slepton and neutralino-sneutrino coannihilation needed in our exploration of the NUHM.Comment: 92 pages LaTeX, 32 eps figures, final version, some changes to figures pertaining to the b to s gamma constrain