A relativistic quantum-mechanical model for a one-dimensionally extended composite hadron is studied in detail. The model is suggested by the string model, and has the same spectrum of excitations in the large-quantum-number limit, but has features which represent departures from the string model as well. The ground state of the system has the character of a conductive medium. Quasiparticle excitations in filled Fermi-sea configurations give rise to towers of particles of increasing mass and spin. Lorentz-scalar collective excitations with Bose statistics are also supported by the system, and can lead to a Hagedorn-type degeneracy in the spectrum. The fundamental dynamical variables of the theory are canonical Fermi fields, but an internal consistency requirement of the theory demands all physical states must have zero fermion ("quark") number. The theory is relativistically covariant in four-dimensional Minkowski space, without requiring ghosts or tachyons.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)