Fractional quantum Hall effect on the two-sphere: a matrix model proposal

We present a Chern-Simons matrix model describing the fractional quantum Hall effect on the two-sphere. We demonstrate the equivalence of our proposal to particular restrictions of the Calogero-Sutherland model, reproduce the quantum states and filling fraction and show the compatibility of our result with the Haldane spherical wavefunctions.Comment: 26 pages, LaTeX, no figures, references adde

Differential Calculus on Fuzzy Sphere and Scalar Field

We find that there is an alternative possibility to define the chirality operator on the fuzzy sphere, due to the ambiguity of the operator ordering. Adopting this new chirality operator and the corresponding Dirac operator, we define Connes' spectral triple on the fuzzy sphere and the differential calculus. The differential calculus based on this new spectral triple is simplified considerably. Using this formulation the action of the scalar field is derived.Comment: LaTeX 12 page

Event-Study Evidence of the Value of Relaxing Longstanding Regulatory Restraints on Banks, 1970-2000

In a partial-equilibrium model, removing a binding constraint creates value. However, in general equilibrium, the stakes of other parties in maintaining the constraint must be examined. In financial deregulation, the fear is that expanding the scope and geographic reach of very large institutions might unblock opportunities to build market power from informational advantages and size-related safety-net subsidies. This paper reviews and extends event-study evidence about the distribution of the benefits and costs of relaxing longstanding geographic and product-line restrictions on U.S. financial institutions. The evidence indicates that the new financial freedoms may have redistributed rather than created value. Event returns are positive for some sectors of the financial industry and negative for others. Perhaps surprisingly, where customer event returns have been investigated, they prove negative.

Monopole Bundles over Fuzzy Complex Projective Spaces

We give a construction of the monopole bundles over fuzzy complex projective spaces as projective modules. The corresponding Chern classes are calculated. They reduce to the monopole charges in the N -> infinity limit, where N labels the representation of the fuzzy algebra.Comment: 30 pages, LaTeX, published version; extended discussion on asymptotic Chern number

On the Quantum Lorentz Group

The quantum analogues of Pauli matrices are introduced and investigated. From these matrices and an appropriate trace over spinorial indiceswe construct a quantum Minkowsky metric. In this framework, we show explicitely the correspondance between the SL(2,C) and Lorentz quantum groups.Comment: 17 page

Boundary state analysis on the equivalence of T-duality and Nahm transformation in superstring theory

We investigated the equivalence of the T-duality for a bound state of D2 and D0-branes with the Nahm transformation of the corresponding gauge theory on a 2-dimensional torus, using the boundary state analysis in superstring theory. In contrast to the case of a 4-dimensional torus, it changes a sign in a topological charge, which seems puzzling when regarded as a D-brane charge. Nevertheless, it is shown that it agrees with the T-duality of the boundary state, including a minus sign. We reformulated boundary states in the RR-sector using a new representation of zeromodes, and show that the RR-coupling is invariant under the T-duality. Finally, the T-duality invariance at the level of the Chern-Simon coupling is shown by deriving the Buscher rule for the RR-potentials, known as the 'Hori formula', including the correct sign.Comment: 31 pages. v2: references added, typos correcte