20 research outputs found
Dyonic Giant Magnons
We study the classical spectrum of string theory on AdS_5 X S^5 in the
Hofman-Maldacena limit. We find a family of classical solutions corresponding
to Giant Magnons with two independent angular momenta on S^5. These solutions
are related via Pohlmeyer's reduction procedure to the charged solitons of the
Complex sine-Gordon equation. The corresponding string states are dual to BPS
boundstates of many magnons in the spin-chain description of planar N=4 SUSY
Yang-Mills. The exact dispersion relation for these states is obtained from a
purely classical calculation in string theory.Comment: LaTeX file, 16 pages. One figure. Corrected reference
Magnons, their Solitonic Avatars and the Pohlmeyer Reduction
We study the solitons of the symmetric space sine-Gordon theories that arise
once the Pohlmeyer reduction has been imposed on a sigma model with the
symmetric space as target. Under this map the solitons arise as giant magnons
that are relevant to string theory in the context of the AdS/CFT
correspondence. In particular, we consider the cases S^n, CP^n and SU(n) in
some detail. We clarify the construction of the charges carried by the solitons
and also address the possible Lagrangian formulations of the symmetric space
sine-Gordon theories. We show that the dressing, or Backlund, transformation
naturally produces solitons directly in both the sigma model and the symmetric
space sine-Gordon equations without the need to explicitly map from one to the
other. In particular, we obtain a new magnon solution in CP^3. We show that the
dressing method does not produce the more general "dyonic" solutions which
involve non-trivial motion of the collective coordinates carried by the
solitons.Comment: 52 page
Soliton Spectrum of Integrable Models with Local Symmetries
The soliton spectrum (massive and massless) of a family of integrable models
with local U(1) and U(1)\otimes U(1) symmetries is studied. These models
represent relevant integrable deformations of SL(2,R) \otimes U(1)^{n-1} - WZW
and SL(2,R) \otimes SL(2,R)\otimes U(1)^{n-2} - WZW models. Their massless
solitons appears as specific topological solutions of the U(1) (or U(1)\otimes
U(1)) - CFTs. The nonconformal analog of the GKO-coset formula is derived and
used in the construction of the composite massive solitons of the ungauged
integrable models.Comment: 44 pages, Latex, 1 eps fig, few misprints corrected. to appear in
JHE