1,454 research outputs found
An exact prediction of [script N] = 4 supersymmetric YangâMills theory for string theory
We propose that the expectation value of a circular BPS-Wilson loop in [script N] = 4 supersymmetric YangâMills can be calculated exactly, to all orders in a 1/N expansion and to all orders in g2N. Using the AdS/CFT duality, this result yields a prediction of the value of the string amplitude with a circular boundary to all orders in alpha[prime] and to all orders in gs. We then compare this result with string theory. We find that the gauge theory calculation, for large g2N and to all orders in the 1/N2 expansion, does agree with the leading string theory calculation, to all orders in gs and to lowest order in alpha[prime]. We also find a relation between the expectation value of any closed smooth Wilson loop and the loop related to it by an inversion that takes a point along the loop to infinity, and compare this result, again successfully, with string theory
D-brane Description of New Open String Solutions in AdS(5)
In this paper we find D-brane descriptions of some of new open string
solutions that were found in 0804.3438[hep-th]. These D5-brane and D3-brane
configurations give gravitational dual descriptions of Wilson loops in some
particular representations.Comment: 13 pages, references adde
Supersymmetric Open Wilson Lines
In this paper we study Open Wilson Lines (OWL's) in the context of two
Supersymmetric Yang Mills theories. First we consider four dimensional N=2
Supersymmetric Yang Mills Theory with hypermultiplets transforming in the
fundamental representation of the gauge group, and find supersymmetric OWL's
only in the superconformal versions of these theories. We then consider four
dimensional N=4 SYM coupled to a three dimensional defect hypermultiplet. Here
there is a semi-circular supersymmetric OWL, which is related to the ray by a
conformal transformation. We perform a perturbative calculation of the
operators in both theories, and discuss using localization to compute them
non-perturbatively.Comment: 26 pages, 3 figure
BPS Wilson Loops on S^2 at Higher Loops
We consider supersymmetric Wilson loops of the variety constructed by
Drukker, Giombi, Ricci, and Trancanelli, whose spatial contours lie on a
two-sphere. Working to second order in the 't Hooft coupling in planar N=4
Supersymmetric Yang-Mills Theory (SYM), we compute the vacuum expectation value
of a wavy-latitude and of a loop composed of two longitudes. We evaluate the
resulting integrals numerically and find that the results are consistent with
the zero-instanton sector calculation of Wilson loops in 2-d Yang-Mills on S^2
performed by Bassetto and Griguolo. We also consider the connected correlator
of two distinct latitudes to third order in the 't Hooft coupling in planar N=4
SYM. We compare the result in the limit where the latitudes become coincident
to a perturbative calculation in 2-d Yang-Mills on S^2 using a light-cone
Wu-Mandelstam-Leibbrandt prescription. We are not able to calculate the SYM
result at the required order in the separation between the latitudes necessary
for a match with 2-d Yang-Mills; the result, however, does not preclude such a
match.Comment: 39 pages, 15 figures. v2 references added, minor cosmetic changes. v3
minor error in eq. (40) corrected. v4 error in coincident limit of correlator
corrected; claims of disagreement with 2-d Yang-Mills retracte
An Exact Prediction of N=4 SUSYM Theory for String Theory
We propose that the expectation value of a circular BPS-Wilson loop in N=4
SUSYM can be calculated exactly, to all orders in a 1/N expansion and to all
orders in g^2 N. Using the AdS/CFT duality, this result yields a prediction of
the value of the string amplitude with a circular boundary to all orders in
alpha' and to all orders in g_s. We then compare this result with string
theory. We find that the gauge theory calculation, for large g^2 N and to all
orders in the 1/N^2 expansion does agree with the leading string theory
calculation, to all orders in g_s and to lowest order in alpha'. We also find a
relation between the expectation value of any closed smooth Wilson loop and the
loop related to it by an inversion that takes a point along the loop to
infinity, and compare this result, again successfully, with string theory.Comment: LaTeX, 22 pages, 3 figures. Argument corrected and two new sections
adde
Green-Schwarz String in AdS_5 x S^5: Semiclassical Partition Function
A systematic approach to the study of semiclassical fluctuations of strings
in AdS_5 x S^5 based on the Green-Schwarz formalism is developed. We show that
the string partition function is well defined and finite. Issues related to
different gauge choices are clarified. We consider explicitly several cases of
classical string solutions with the world surface ending on a line, on a circle
or on two lines on the boundary of AdS. The first example is a BPS object and
the partition function is one. In the third example the determinants we derive
should give the first corrections to the Wilson loop expectation value in the
strong coupling expansion of the n=4 SYM theory at large N.Comment: 61 pages, harvmac, minor change
Semi-classical open string corrections and symmetric Wilson loops
In the AdS/CFT correspondence, an AdS_2 x S^2 D3-brane with electric flux in
AdS_5 x S^5 spacetime corresponds to a circular Wilson loop in the symmetric
representation or a multiply wound one in N=4 super Yang-Mills theory. In order
to distinguish the symmetric loop and the multiply wound loop, one should see
an exponentially small correction in large 't Hooft coupling. We study
semi-classically the disk open string attached to the D3-brane. We obtain the
exponent of the term and it agrees with the result of the matrix model
calculation of the symmetric Wilson loop.Comment: 14 pages, 4 figures. v2: explanation improved. v3: argument in
section 2 is improved, result not change
Impure Aspects of Supersymmetric Wilson Loops
We study a general class of supersymmetric Wilson loops operator in N = 4
super Yang-Mills theory, obtained as orbits of conformal transformations. These
loops are the natural generalization of the familiar circular Wilson-Maldacena
operator and their supersymmetric properties are encoded into a Killing spinor
that is not pure. We present a systematic analysis of their scalar couplings
and of the preserved supercharges, modulo the action of the global symmetry
group, both in the compact and in the non-compact case. The quantum behavior of
their expectation value is also addressed, in the simplest case of the
Lissajous contours: explicit computations at weak-coupling, through Feynman
diagrams expansion, and at strong-coupling, by means of AdS/CFT correspondence,
suggest the possibility of an exact evaluation.Comment: 40 pages, 4 figure
An exact formula for the radiation of a moving quark in N=4 super Yang Mills
We derive an exact formula for the cusp anomalous dimension at small angles.
This is done by relating the latter to the computation of certain 1/8 BPS
Wilson loops which was performed by supersymmetric localization. This function
of the coupling also determines the power emitted by a moving quark in N=4
super Yang Mills, as well as the coefficient of the two point function of the
displacement operator on the Wilson loop. By a similar method we compute the
near BPS expansion of the generalized cusp anomalous dimension.Comment: 22 pages, 5 figures. v2: references added, typos correcte
A note on perturbation series in supersymmetric gauge theories
Exact results in supersymmetric Chern-Simons and N=2 Yang-Mills theories can
be used to examine the quantum behavior of observables and the structure of the
perturbative series. For the U(2) x U(2) ABJM model, we determine the
asymptotic behavior of the perturbative series for the partition function and
write it as a Borel transform. Similar results are obtained for N=2 SU(2) super
Yang-Mills theory with four fundamental flavors and in N=2* super Yang-Mills
theory, for the partition function as well as for the expectation values for
Wilson loop and 't Hooft loop operators (in the 0 and 1 instanton sectors). In
all examples, one has an alternate perturbation series where the coefficient of
the nth term increases as n!, and the perturbation series are Borel summable.
We also calculate the expectation value for a Wilson loop operator in the N=2*
SU(N) theory at large N in different regimes of the 't Hooft gauge coupling and
mass parameter. For large masses, the calculation reproduces the running gauge
coupling for the pure N=2 SYM theory.Comment: 28 pages. V2: minor additions and reference adde
- âŠ