496 research outputs found
Exact 1/4 BPS Loop - Chiral Primary Correlator
Correlation functions of 1/4 BPS Wilson loops with the infinite family of 1/2
BPS chiral primary operators are computed in super Yang-Mills
theory by summing planar ladder diagrams. Leading loop corrections to the sum
are shown to vanish. The correlation functions are also computed in the
strong-coupling limit by examining the supergravity dual of the loop-loop
correlator. The strong coupling result is found to agree with the extrapolation
of the planar ladders. The result is related to known correlators of 1/2 BPS
Wilson loops and 1/2 BPS chiral primaries by a simple re-scaling of the
coupling constant, similar to an observation of Drukker, hep-th/0605151, for
the case of the 1/4 BPS loop vacuum expectation value.Comment: 17 pages, 4 figures, a few minor typos correcte
More exact predictions of SUSYM for string theory
We compute the coefficients of an infinite family of chiral primary operators
in the local operator expansion of a circular Wilson loop in N=4 supersymmetric
Yang-Mills theory. The computation sums all planar rainbow Feynman graphs. We
argue that radiative corrections from planar graphs with internal vertices
cancel in leading orders and we conjecture that they cancel to all orders in
perturbation theory. The coefficients are non-trivial functions of the 'tHooft
coupling and their strong coupling limits are in exact agreement with those
previously computed using the AdS/CFT correspondence. They predict the
subleading orders in strong coupling and could in principle be compared with
string theory calculations.Comment: 14 pages, 3 figures; v2: misprints correcte
Open string fluctuations in AdS_5xS^5 and operators with large R-charge
A semiclassical string description is given for correlators of Wilson loops
with local operators in N=4 SYM theory in the regime when operators carry
parametrically large R-charge. The OPE coefficients of the circular Wilson loop
in chiral primary operators are computed to all orders in the alpha' expansion
in AdS_5xS^5 string theory. The results agree with field-theory predictions.Comment: 16 pages, 2 figures; v2: five misprints correcte
Wilson loops in SYM theory: from weak to strong coupling
We review Wilson loops in N=4 supersymmetric Yang-Mills theory with emphasis
on the exact results. The implications are discussed in the context of the
AdS/CFT correspondence.Comment: 32 pages, 5 figure
Rationalizing virtual reality based on manufacturing paradigms
Comparing the evolvement of the manufacturing industry of the last century to the way virtual reality is used nowadays some remarkable similarities come to light. Current virtual reality equipment requires a high level of craftsmanship to achieve the maximum results, and often equipment is specially build for a dedicated process or project. While the technical revolution in the manufacturing industry led to a turnaround in which more generic production equipment were used in a structured configuration. The goal is to prevent the pitfalls already encountered in the last century in process planning, and convert the advantages of a reconfigurable manufacturing system to the way virtual reality is used
The generalized cusp in ABJ(M) N = 6 Super Chern-Simons theories
We construct a generalized cusped Wilson loop operator in N = 6 super
Chern-Simons-matter theories which is locally invariant under half of the
supercharges. It depends on two parameters and interpolates smoothly between
the 1/2 BPS line or circle and a pair of antiparallel lines, representing a
natural generalization of the quark-antiquark potential in ABJ(M) theories. For
particular choices of the parameters we obtain 1/6 BPS configurations that,
mapped on S^2 by a conformal transformation, realize a three-dimensional
analogue of the wedge DGRT Wilson loop of N = 4. The cusp couples, in addition
to the gauge and scalar fields of the theory, also to the fermions in the
bifundamental representation of the U(N)xU(M) gauge group and its expectation
value is expressed as the holonomy of a suitable superconnection. We discuss
the definition of these observables in terms of traces and the role of the
boundary conditions of fermions along the loop. We perform a complete two-loop
analysis, obtaining an explicit result for the generalized cusp at the second
non-trivial order, from which we read off the interaction potential between
heavy 1/2 BPS particles in the ABJ(M) model. Our results open the possibility
to explore in the three-dimensional case the connection between localization
properties and integrability, recently advocated in D = 4.Comment: 53 pages, 10 figures, added references, this is the version appeared
on JHE
Nonperturbative aspects of ABJM theory
Using the matrix model which calculates the exact free energy of ABJM theory
on S^3 we study non-perturbative effects in the large N expansion of this
model, i.e., in the genus expansion of type IIA string theory on AdS4xCP^3. We
propose a general prescription to extract spacetime instanton actions from
general matrix models, in terms of period integrals of the spectral curve, and
we use it to determine them explicitly in the ABJM matrix model, as exact
functions of the 't Hooft coupling. We confirm numerically that these
instantons control the asymptotic growth of the genus expansion. Furthermore,
we find that the dominant instanton action at strong coupling determined in
this way exactly matches the action of an Euclidean D2-brane instanton wrapping
RP^3.Comment: 26 pages, 14 figures. v2: small corrections, final version published
in JHE
Wilson Loops in N=4 SYM and Fermion Droplets
The matrix models which are conjectured to compute the circle Wilson loop and
its correlator with chiral primary operators are mapped onto normal matrix
models. A fermion droplet picture analogous to the well-known one for chiral
primary operators is shown to emerge in the large N limit. Several examples are
computed. We find an interesting selection rule for the correlator of a single
trace Wilson loop with a chiral primary operator. It can be non-zero only if
the chiral primary is in a representation with a single hook. We show that the
expectation value of the Wilson loop in a large representation labelled by a
Young diagram with a single row has a first order phase transition between a
regime where it is identical to a large column representation and a regime
where it is a large wrapping number single trace Wilson loop.Comment: 32 pages, 2 figure
Comparing strings in AdS(5)xS(5) to planar diagrams: an example
The correlator of a Wilson loop with a local operator in N=4 SYM theory can
be represented by a string amplitude in AdS(5)xS(5). This amplitude describes
an overlap of the boundary state, which is associated with the loop, with the
string mode, which is dual to the local operator. For chiral primary operators
with a large R charge, the amplitude can be calculated by semiclassical
techniques. We compare the semiclassical string amplitude to the SYM
perturbation theory and find an exact agrement to the first two non-vanishing
orders.Comment: 16 pages, 4 figures, LaTeX; v2: typos corrected; v3: clarification of
boundary conditions at infinity adde
Goedel's Universe in a Supertube Shroud
We demonstrate that certain supersymmetric Goedel-like universe solutions of
supergravity are not solutions of string theory. This is achieved by realizing
that supertubes are BPS states in these spaces, and under certain conditions,
when wrapping closed timelike curves, some world-volume modes develop negative
kinetic terms. Since these universes are homogeneous, this instability takes
place everywhere in space-time. We also construct a family of supergravity
solutions which locally look like the Goedel universe inside a domain wall made
out of supertubes, but have very different asymptotic structure. One can adjust
the volume inside the domain wall so there will be no closed timelike curves,
and then those spaces seem like perfectly good string backgrounds.Comment: 4 pages, revtex double column. v2: corrected the metric outside the
domain wal
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