320 research outputs found
Pseudo-hermitian interaction between an oscillator and a spin half particle in the external magnetic field
We consider a spin half particle in the external magnetic field which couples
to a harmonic oscillator through some pseudo-hermitian interaction. We find
that the energy eigenvalues for this system are real even though the
interaction is not PT invariant.Comment: Latex, no figs, 8 pages. (To appear in Mod. Phys. Lett. A
Dual giant gravitons in AdS Y (Sasaki-Einstein)
We consider BPS motion of dual giant gravitons on Ad where
represents a five-dimensional Sasaki-Einstein manifold. We find that the
phase space for the BPS dual giant gravitons is symplectically isomorphic to
the Calabi-Yau cone over , with the K\"{a}hler form identified with the
symplectic form. The quantization of the dual giants therefore coincides with
the K\"{a}hler quantization of the cone which leads to an explicit
correspondence between holomorphic wavefunctions of dual giants and
gauge-invariant operators of the boundary theory. We extend the discussion to
dual giants in where is a seven-dimensional
Sasaki-Einstein manifold; for special motions the phase space of the dual
giants is symplectically isomorphic to the eight-dimensional Calabi-Yau cone.Comment: 14 pages. (v2) typo's corrected; factors of AdS radius reinstated for
clarity; remarks about dual giant wavefunctions in T^{1,1} expanded and put
in a new subsectio
Supersymmetric Electromagnetic Waves on Giants and Dual-Giants
We set up the BPS equations for a D3-brane moving in AdS_5 \times S^5 which
preserves two supercharges and with all bosonic fields turned on in the
world-volume theory. By solving these, we find generalizations of Mikhailov
giants and wobbling dual-giants that include electromagnetic waves propagating
on their world-volume. For these giants (dual-giants) we show that the BPS
field strength is the real part of the pull-back of a holomorphic 2-form in the
ambient space C^3 (C^{1,2}) onto the world-volume.Comment: 18 page
Supersymmetric States in M5/M2 CFTs
We propose an exact, finite formula for the partition function over
BPS states in the conformal field theory on the world volume of
coincident M5 branes and BPS states in the theory of coincident
M2 branes. We obtain our partition function by performing the radial
quantization of the Coulomb Branches of these theories, and rederive the same
formula from the quantization of supersymmetric giant and dual giant gravitons
in and . Our partition function is
qualitatively similar to the analogous quantity in Yang Mills. It
reduces to the sum over supersymmetric multi gravitons at low energies, but
deviates from this supergravity formula at energies that scale like a positive
power of .Comment: 24 pages, harvmac; v2 reference adde
Classical integrability in the BTZ black hole
Using the fact the BTZ black hole is a quotient of AdS_3 we show that
classical string propagation in the BTZ background is integrable. We construct
the flat connection and its monodromy matrix which generates the non-local
charges. From examining the general behaviour of the eigen values of the
monodromy matrix we determine the set of integral equations which constrain
them. These equations imply that each classical solution is characterized by a
density function in the complex plane. For classical solutions which correspond
to geodesics and winding strings we solve for the eigen values of the monodromy
matrix explicitly and show that geodesics correspond to zero density in the
complex plane. We solve the integral equations for BMN and magnon like
solutions and obtain their dispersion relation. Finally we show that the set of
integral equations which constrain the eigen values of the monodromy matrix can
be identified with the continuum limit of the Bethe equations of a twisted
SL(2, R) spin chain at one loop.Comment: 45 pages, Reference added, typos corrected, discussion on geodesics
improved to include all geodesic
Free Fermions and Thermal AdS/CFT
The dynamics of finite temperature U(N) gauge theories on can be
described, at weak coupling, by an effective unitary matrix model. Here we
present an exact solution to these models, for any value of , in terms of a
sum over representations. Taking the large limit of this solution provides
a new perspective on the deconfinement transition which is supposed to be dual
to the Hawking-Page transition. The large phase transition manifests itself
here in a manner similar to the Douglas-Kazakov phase transition in 2d
Yang-Mills theory. We carry out a complete analysis of the saddle
representation in the simplest case involving only the order parameter . We find that the saddle points corresponding to thermal , the small
black hole and the large black hole can all be described in terms of free
fermions. They all admit a simple phase space description {\it a la} the BPS
geometries of Lin, Lunin and Maldacena.Comment: (0+34) pages and 9 figures, v2 references adde
Baryonic Generating Functions
We show how it is possible to use the plethystic program in order to compute
baryonic generating functions that count BPS operators in the chiral ring of
quiver gauge theories living on the world volume of D branes probing a non
compact CY manifold. Special attention is given to the conifold theory and the
orbifold C^2/Z_2 times C, where exact expressions for generating functions are
given in detail. This paper solves a long standing problem for the
combinatorics of quiver gauge theories with baryonic moduli spaces. It opens
the way to a statistical analysis of quiver theories on baryonic branches.
Surprisingly, the baryonic charge turns out to be the quantized Kahler modulus
of the geometry.Comment: 44 pages, 7 figures; fonts change
At the horizon of a supersymmetric AdS_5 black hole: Isometries and half-BPS giants
The near-horizon geometry of an asymptotically AdS_5 supersymmetric black
hole discovered by Gutowski and Reall is analysed. After lifting the solution
to 10 dimensions, we explicitly solve the Killing spinor equations in both
Poincare and global coordinates. It is found that exactly four supersymmetries
are preserved which is twice the number for the full black hole. The full set
of isometries is constructed and the isometry supergroup is shown to be
SU(1,1|1) X SU(2) X U(3). We further study half-BPS configurations of D3-branes
in the near-horizon geometry in Poincare and global coordinates. Both giant
graviton probes and dual giant graviton probes are found.Comment: 26 pages. v2:Typos corrected, minor change
Toric AdS4/CFT3 duals and M-theory Crystals
We study the recently proposed crystal model for three dimensional
superconformal field theories arising from M2-branes probing toric Calabi-Yau
four-fold singularities. We explain the algorithms mapping a toric Calabi-Yau
to a crystal and vice versa, and show how the spectrum of BPS meson states fits
into the crystal model.Comment: 24 pages, 24 figure
Logarithmic Corrections to Schwarzschild and Other Non-extremal Black Hole Entropy in Different Dimensions
Euclidean gravity method has been successful in computing logarithmic
corrections to extremal black hole entropy in terms of low energy data, and
gives results in perfect agreement with the microscopic results in string
theory. Motivated by this success we apply Euclidean gravity to compute
logarithmic corrections to the entropy of various non-extremal black holes in
different dimensions, taking special care of integration over the zero modes
and keeping track of the ensemble in which the computation is done. These
results provide strong constraint on any ultraviolet completion of the theory
if the latter is able to give an independent computation of the entropy of
non-extremal black holes from microscopic description. For Schwarzschild black
holes in four space-time dimensions the macroscopic result seems to disagree
with the existing result in loop quantum gravity.Comment: LaTeX, 40 pages; corrected small typos and added reference
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