Fractional quantum Hall effect in nonuniform magnetic fields.

Investigations of the fractional quantum Hall effect are extended to spatially varying magnetic fields. Approximate single-particle wave functions are proposed and compared with ones obtained by numerical integration. As in the uniform field case, the interacting many-electron system forms an incompressible fluid and has fractionally charged excitations. Field inhomogeneities can trap collective excitations. © 1990 The American Physical Society

Equivalence of lattice gauge and spin theories

It is shown that a lattice gauge theory based on the group G is equivalent to a lattice spin theory invariant under a global group which is an infinite direct product of G's. A method of inducing a lattice gauge theory is presented. © 1983

Photoproduction of intermediate vector bosons

A peripheral collision calculation of the process γ + p → W + ..., where W is an intermediate vector boson, is performed. Results and possible detection schemes are discussed. © 1963

Current-algebra sum rules for states of arbitrary mass and spin

Sum rules based on current algebra are obtained for the currents evaluated between states of arbitrary spin and mass. Both the infinite-momentum limit and the dispersion method are shown to yield the same result. These sum rules are given explicitly for the crossed-channel amplitudes. © 1967 The American Physical Society

Isospin mixing in charmonium states

The "molecular" charmonium models predict both I = 0 and I = 1 states. The closeness of one of these (4.028 GeV) to one of its main thresholds and the large electromagnetic mass splitting of its daughters may induce a large mixing between states of different isospin. This would manifest itself in deviations from unity of the ratio of charged to neutral decay modes. © 1977 The American Physical Society

Multiple vacua for non-abelian lattice gauge theories

The various formulations of gauge theories characterized by the parameter θ are constructed for the lattice version of these theories. We do not rely on the existence of topologically stable solutions of the classical equations. These constructions are based on the existence of inequivalent representations of the canonical commutation relations. © 1979

Boson-fermion correspondence in two-dimensional field theories

The correspondence between boson and fermion field theories in one space and one time dimension is examined in the context of a path-integral formulation of these theories. The advantage of this formulation is that the translation, both for the Lagrangians and the field operators, is fairly automatic. Normalization of products of fields, which in more conventional formulations required careful manipulation of singular quantities, in this approach is a straightforward consequence of Lorentz invariance. © 1976 The American Physical Society

Multiparticle production-Feynman fluid analogy

The analogy between high-energy events with many particles in the final state and a distribution of particles in a fluid is examined in detail. It is shown that many theoretical models lend themselves to such an interpretation. Using experimental data on prong cross sections and one-particle inclusive distributions, some properties of this analogous fluid are computed. The possibility and significance of a "phase transition" are discussed and predictions based on such considerations are made for higher energies. © 1972 The American Physical Society

The two-dimensional hydrogen atom revisited

The bound state energy eigenvalues for the two-dimensional Kepler problem are found to be degenerate. This "accidental" degeneracy is due to the existence of a two-dimensional analogue of the quantum-mechanical Runge-Lenz vector. Reformulating the problem in momentum space leads to an integral form of the Schroedinger equation. This equation is solved by projecting the two-dimensional momentum space onto the surface of a three-dimensional sphere. The eigenfunctions are then expanded in terms of spherical harmonics, and this leads to an integral relation in terms of special functions which has not previously been tabulated. The dynamical symmetry of the problem is also considered, and it is shown that the two components of the Runge-Lenz vector in real space correspond to the generators of infinitesimal rotations about the respective coordinate axes in momentum space.Comment: 10 pages, no figures, RevTex

Gravity in Dynamically Generated Dimensions

A theory of gravity in $d+1$ dimensions is dynamically generated from a theory in $d$ dimensions. As an application we show how $N$ dynamically coupled gravity theories can reduce the effective Planck mass.Comment: 7 pages, LaTeX (Revtex