Spectral functions in a magnetic field as a probe of spin-charge separation in a Luttinger liquid

We show that the single-particle spectral functions in a magnetic field can be used to probe spin-charge separation of a Luttinger liquid. Away from the Fermi momentum, the magnetic field splits both the spinon peak and holon peak; here the spin-charge separation nature is reflected in the different magnitude of the two splittings. At the Fermi momentum, the magnetic field splits the zero-field peak into {\it four} peaks. The feasibility of experimentally studying this effect is discussed.Comment: 4 pages, 3 figures; published versio

BFV Quantization of Relativistic Spinning Particles with a Single Bosonic Constraint

Using the BFV approach we quantize a pseudoclassical model of the spin one half relativistic particle that contains a single bosonic constraint, contrary to the usual locally supersymmetric models that display first and second class constraints.Comment: 5 p., Latex, IF-UFRJ-94-1

An operator approach to BRST invariant transition amplitudes

The transition amplitudes for the free spinless and spinning relativistic particles are obtained by applying an operator method developed long ago by Dirac and Schwinger to the BFV form of the BRST theory for constrained systems.Comment: 10 pages, Latex, IF-UFRJ-9