215 research outputs found
Free Energies and Probe Actions for Near-horizon D-branes and D1 + D5 System
By working with the free energy for the type II supergravity near-horizon
solution of N coincident non-extremal Dp-branes we study the transitions among
the non-conformal Dp-brane system, the perturbative super Yang-Mills theory and
a certain system associated with M theory. We derive a relation between this
free energy and the action of a Dp-brane probe in the N Dp-brane background.
Constructing the free energy for the five dimensional black hole labeled by the
D1-brane and D5-brane charges we find the similar relation between it and the
action of a D1 or D5 brane probe in the D1 + D5 brane background. These
relations are explained by the massive open strings stretched between the
relevant D-branesComment: 14 pages, LaTeX2e, no figure
Infinite spin limit of semiclassical string states
Motivated by recent works of Hofman and Maldacena and Dorey we consider a
special infinite spin limit of semiclassical spinning string states in AdS5 x
S5. We discuss examples of known folded and circular 2-spin string solutions
and demonstrate explicitly that the 1-loop superstring correction to the
classical expression for the energy vanishes in the limit when one of the spins
is much larger that the other. We also give a general discussion of this limit
at the level of integral equations describing finite gap solutions of the
string sigma model and argue that the corresponding asymptotic form of the
string and gauge Bethe equations is the same.Comment: 38 pages, 3 figures; v2: comments on derivation of bound states of
magnons from discrete Bethe equations added in section 4 and appendix C,
references added, Imperial-TP-AT-6-4, HUTP-06/A002
Spiky Strings on I-brane
We study rigidly rotating strings in the near horizon geometry of the 1+1
dimensional intersection of two orthogonal stacks of NS5-branes, the so called
I-brane background. We solve the equations of motion of the fundamental string
action in the presence of two form NS-NS fluxes that the I-brane background
supports and write down general form of conserved quantities. We further find
out two limiting cases corresponding to giant magnon and single spike like
strings in various parameter space of solutions.Comment: 17 pages, major restructuring of text, added a referenc
Three Spin Spiky Strings in beta-deformed Background
We study rigidly rotating strings in -deformed
background with one spin along AdS and two angular momenta along . We
find the spiky string solutions and present the dispersion relation among
various charges in this background. We further generalize the result to the
case of four angular momenta along .Comment: 12 pages, minor corrections, added references, to appear in JHE
Spiky strings and single trace operators in gauge theories
We consider single trace operators of the form O_{m_1 ... m_n} = tr D_+^{m_1}
F ... D_+^{m_n} F which are common to all gauge theories. We argue that, when
all m_i are equal and large, they have a dual description as strings with
cusps, or spikes, one for each field F. In the case of N=4 SYM, we compute the
energy as a function of angular momentum by finding the corresponding solutions
in AdS_5 and compare with a 1-loop calculation of the anomalous dimension. As
in the case of two spikes (twist two operators), there is agreement in the
functional form but not in the coupling constant dependence. After that, we
analyze the system in more detail and find an effective classical mechanics
describing the motion of the spikes. In the appropriate limit, it is the same
(up to the coupling constant dependence) as the coherent state description of
linear combinations of the operators O_{m_1 ... m_n} such that all m_i are
equal on average. This agreement provides a map between the operators in the
boundary and the position of the spikes in the bulk. We further suggest that
moving the spikes in other directions should describe operators with
derivatives other than D_+ indicating that these ideas are quite generic and
should help in unraveling the string description of the large-N limit of gauge
theories.Comment: 23 pages, 5 figures. v2: References and comments adde
Conformal SO(2,4) Transformations for the Helical AdS String Solution
By applying the conformal SO(2,4) transformations to the folded rotating
string configuration with two spins given by a certain limit from the helical
string solution in AdS_3 x S^1, we construct new string solutions whose
energy-spin relations are characterized by the boost parameter. When two
SO(2,4) transformations are performed with two boost parameters suitably
chosen, the straight folded rotating string solution with one spin in AdS_3 is
transformed in the long string limit into the long spiky string solution whose
expression is given from the helical string solution in AdS_3 by making a limit
that the modulus parameter becomes unity.Comment: 16 pages, LaTex, no figure
Constant mean curvature surfaces in AdS_3
We construct constant mean curvature surfaces of the general finite-gap type
in AdS_3. The special case with zero mean curvature gives minimal surfaces
relevant for the study of Wilson loops and gluon scattering amplitudes in N=4
super Yang-Mills. We also analyze properties of the finite-gap solutions
including asymptotic behavior and the degenerate (soliton) limit, and discuss
possible solutions with null boundaries.Comment: 19 pages, v2: minor corrections, to appear in JHE
Three-point correlators for giant magnons
Three-point correlation functions in the strong-coupling regime of the
AdS/CFT correspondence can be analyzed within a semiclassical approximation
when two of the vertex operators correspond to heavy string states having large
quantum numbers while the third vertex corresponds to a light state with fixed
charges. We consider the case where the heavy string states are chosen to be
giant magnon solitons with either a single or two different angular momenta,
for various different choices of light string states.Comment: 15 pages. Latex. v2: Misprints corrected. Published versio
Rotating Strings with Two Unequal Spins in Lunin-Maldacena Background
We study a string motion in the Lunin-Maldacena background, that is, the
\beta-deformed AdS_5 \times \tilde{S}^5 background dual to a \beta-deformation
of \mathcal{N} = 4 super Yang-Mills theory. For real \beta we construct a
rotating and wound string solution which has two unequal spins in \tilde{S}^5.
The string energy is expressed in terms of the spins, the winding numbers and
the deformation parameter. In the expansion of \lambda/J^2 with the total spin
J and the string tension \sqrt{\lambda} we present ``one-loop" and ``two-loop"
energy corrections. The ``one-loop" one agrees with the one-loop anomalous
dimension of the corresponding gauge-theory scalar operators obtained in
hep-th/0503192 from the \beta-deformed Bethe equation as well as the
anisotropic Landau-Lifshitz equation.Comment: 13 pages, LaTeX, no figure
Circular and Folded Multi-Spin Strings in Spin Chain Sigma Models
From the SU(2) spin chain sigma model at the one-loop and two-loop orders we
recover the classical circular string solution with two S^5 spins (J_1, J_2) in
the AdS_5 x S^5 string theory. In the SL(2) sector of the one-loop spin chain
sigma model we explicitly construct a solution which corresponds to the folded
string solution with one AdS_5 spin S and one S^5 spin J. In the one-loop
general sigma model we demonstrate that there exists a solution which
reproduces the energy of the circular constant-radii string solution with three
spins (S_1, S_2, J).Comment: 16 pages, LaTeX, no figure
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