A variational principle for actions on symmetric symplectic spaces

We present a definition of generating functions of canonical relations, which are real functions on symmetric symplectic spaces, discussing some conditions for the presence of caustics. We show how the actions compose by a neat geometrical formula and are connected to the hamiltonians via a geometrically simple variational principle which determines the classical trajectories, discussing the temporal evolution of such ``extended hamiltonians'' in terms of Hamilton-Jacobi-type equations. Simplest spaces are treated explicitly.Comment: 28 pages. Edited english translation of first author's PhD thesis (2000

Hadronic molecules: meson-baryon hybrids

The existence of hadronic molecular-type hybrids consisting of a baryon and a meson is argued. Long-range interactions due to one-pion exchange is shown to be strong enough to produce a loosely bound state. Specific features of a molecular hybrid are discussed.Comment: 7 pages in RevTeX plus 1 figure (available upon request