Multibaryons with strangeness, charm and bottom

Static properties of multiskyrmions with baryon numbers up to 8 are calculated, including momenta of inertia and sigma-term. The calculations are based on the recently suggested SU(2) rational map ansaetze. Minimization with the help of SU(3) variational minimization program shows that these configurations become local minima in SU(3) configuration space. The B-number dependence of the so called flavour moment of inertia of multiskyrmions playing an important role in the quantization procedure is close to the linear one. The spectra of baryonic systems with strangeness, charm and bottom are considered within a "rigid oscillator" version of the bound state soliton model. The binding energies estimates are made for the states with largest isospin which can appear as negatively charged nuclear fragments, as well as for states with zero isospin - light fragments of "flavoured" nuclear matter. Our results confirm the previously made observation that baryonic systems with charm or bottom quantum numbers have more chance to be stable with respect to strong interactions than strange baryonic systems.Comment: 13 pages, no figures. Submitted to Eur. Phys.

Phase spaces related to standard classical rr-matrices

Fundamental representations of real simple Poisson Lie groups are Poisson actions with a suitable choice of the Poisson structure on the underlying (real) vector space. We study these (mostly quadratic) Poisson structures and corresponding phase spaces (symplectic groupoids).Comment: 20 pages, LaTeX, no figure

Low Energy States in the SU(N) Skyrme Models

We show that any solution of the SU(2) Skyrme model can be used to give a topologically trivial solution of the SU(4) one. In addition, we extend the method introduced by Houghton et al. and use harmonic maps from S2 to CP(N-1) to construct low energy configurations of the SU(N) Skyrme models. We show that one of such maps gives an exact, topologically trivial, solution of the SU(3) model. We study various properties of these maps and show that, in general, their energies are only marginally higher than the energies of the corresponding SU(2) embeddings. Moreover, we show that the baryon (and energy) densities of the SU(3) configurations with baryon number B=2-4 are more symmetrical than their SU(2) analogues. We also present the baryon densities for the B=5 and B=6 configurations and discuss their symmetries.Comment: latex : 25 pages, 9 Postscript figures, uses eps

Electrons on Hexagonal Lattices and Applications to Nanotubes

We consider a Fröhlich-type Hamiltonian on a hexagonal lattice. Aiming to describe nanotubes, we choose this two-dimensional lattice to be periodic and to have a large extension in one (x) direction and a small extension in the other (y) direction. We study the existence of solitons in this model using both analytical and numerical methods. We find exact solutions of our equations and discuss some of their properties

A discrete phi^4 system without Peierls-Nabarro barrier

A discrete phi^4 system is proposed which preserves the topological lower bound on the kink energy. Existence of static kink solutions saturating this lower bound and occupying any position relative to the lattice is proved. Consequently, kinks of the model experience no Peierls-Nabarro barrier, and can move freely through the lattice without being pinned. Numerical simulations reveal that kink dynamics in this system is significantly less dissipative than that of the conventional discrete phi^4 system, so that even on extremely coarse lattices the kink behaves much like its continuum counterpart. It is argued, therefore, that this is a natural discretization for the purpose of numerically studying soliton dynamics in the continuum phi^4 model.Comment: 8 pages, LaTeX, 8 postscript figure