5,389 research outputs found
(p,q)-string in matrix-regularized membrane and type IIB duality
We consider a lightcone wrapped supermembrane compactified on 2-torus in the
matrix regularization. We examine the double dimensional reduction technique
and deduce the free matrix string of (p,q)-string in type IIB superstring
theory explicitly from the matrix-regularized wrapped supermembrane. In
addition we obtain the (2+1)-dimensional super Yang-Mills action in curved
background. We also examine the duality.Comment: 25 page
Wrapped membranes, matrix string theory and an infinite dimensional Lie algebra
We examine the algebraic structure of the matrix regularization for the
wrapped membrane on in the light-cone gauge. We give a
concrete representation for the algebra and obtain the matrix string theory
having the boundary conditions for the matrix variables corresponding to the
wrapped membrane, which is referred to neither Seiberg and Sen's arguments nor
string dualities. We also embed the configuration of the multi-wrapped membrane
in matrix string theory.Comment: 19 pages, 1 figure, references added, minor change
Exceptional sheaves on the Hirzebruch surface Fâ‚‚
We investigate exceptional sheaves on the Hirzebruch surface ,
as the first attempt toward the classification of exceptional objects on weak
del Pezzo surfaces.Comment: 25 page
Comments on the global constraints in light-cone string and membrane theories
In the light-cone closed string and toroidal membrane theories, we associate
the global constraints with gauge symmetries. In the closed string case, we
show that the physical states defined by the BRS charge satisfy the
level-matching condition. In the toroidal membrane case, we show that the
Faddeev-Popov ghost and anti-ghost corresponding to the global constraints are
essentially free even if we adopt any gauge fixing condition for the local
constraint. We discuss the quantum double-dimensional reduction of the wrapped
supermembrane with the global constraints.Comment: 12 pages, typos corrected, to appear in JHE
Observation of a charmonium-like enhancement in the gamma gamma --> omega J/psi process
We report the results of a search for a charmonium-like state produced in the
process gamma gamma --> omega J/psi in the 3.9-4.2 GeV/c^2 mass region. We
observe a significant enhancement, which is well-described by a resonant shape
with mass M = (3915 +/- 3 +/- 2) MeV/c^2 and total width Gamma = (17 +/- 10 +/-
3) MeV. This enhancement may be related to one or more of the three
charmonium-like states so far reported in the 3.90-3.95 GeV/c^2 mass region.Comment: 6 pages, 4 figure
Spontaneous Breakdown of U(1) symmetry in DLCQ without Zero Mode
We show that the spontaneous breakdown of U(1) symmetry in a Higgs model can
be described in discretized light cone formulation even by neglecting zero
mode. We obtain correctly the energy of a ground state with the symmetry
breakdown. We also show explicitly the presence of a Goldstone mode and its
absence when the U(1) symmetry is gauged. In spite of obtaining the favorable
results, we lose a merit in the formulation without zero modes that a naive
Fock vacuum is the true ground state.Comment: 7 page
Spin-dependent Polarizability of Nucleon with Dispersion Relation in the Skyrme Model
We calculate the spin-dependent polarizability of the nucleon in the Skyrme
model. The result is compared with that of a heavy baryon chiral perturbation
theory(HBChPT), and is shown to be the same as that of HBChPT up to the
-pole terms in the narrow width limit of the state and with
the experimental physical constants. The effect of the channel is
rather small and is numerically quite similar to that of the loop in
the HBChPT. The electric and magnetic polarizabilities are recalculated using
the transverse photon and a consistent inclusion of the width.Comment: 11 pages, LaTeX, no figures. misprints correcte
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