50 research outputs found
BRST Invariance of Non-local Charges and Monodromy Matrix of Bosonic String on AdS(5)xS(5)
Using the generalized Hamiltonian method of Batalin, Fradkin and Vilkovsky we
develop the BRST formalism for the bosonic string on AdS(5)xS(5) formulated as
principal chiral model. Then we show that the monodromy matrix and non-local
charges are BRST invariant.Comment: 26. page
The Pure Spinor Formulation of Superstrings
In this lectures we outline the construction of pure spinor superstrings. We
consider both the open and closed pure spinor superstrings in critical and
noncritical dimensions and on flat and curved target spaces with RR flux. We
exhibit the integrability properties of pure spinor superstrings on curved
backgrounds with RR fluxes.Comment: These lectures have been given in the RTN Winter School on Strings,
Supergravity and Gauge Theories, CERN (2008). 32 pages, a typo correcte
Algebra of Lax Connection for T-Dual Models
We study relation between T-duality and integrability. We develop the
Hamiltonian formalism for principal chiral model on general group manifold and
on its T-dual image. We calculate the Poisson bracket of Lax connections in
T-dual model and we show that they are non-local as opposite to the Poisson
brackets of Lax connection in original model. We demonstrate these calculations
on two specific examples: Sigma model on S(2) and sigma model on AdS(2).Comment: 24 pages, references adde
Quantum Current Algebra for the Superstring
The sigma model describing the dynamics of the superstring in the background can be constructed using the coset
. A basic set of operators in this two
dimensional conformal field theory is composed by the left invariant currents.
Since these currents are not (anti) holomorphic, their OPE's is not determined
by symmetry principles and its computation should be performed perturbatively.
Using the pure spinor sigma model for this background, we compute the one-loop
correction to these OPE's. We also compute the OPE's of the left invariant
currents with the energy momentum tensor at tree level and one loop.Comment: 28 pages, 12 figures, v2: typos corrected
The Classical Exchange Algebra of AdS5 x S5 String Theory
The classical exchange algebra satisfied by the monodromy matrix of AdS5 x S5
string theory in the Green-Schwarz formulation is determined by using a
first-order Hamiltonian formulation and by adding to the Bena-Polchinski-Roiban
Lax connection terms proportional to constraints. This enables in particular to
show that the conserved charges of this theory are in involution. This result
is obtained for a general world-sheet metric. The same exchange algebra is
obtained within the pure spinor description of AdS5 x S5 string theory. These
results are compared to the one obtained by A. Mikhailov and S. Schaefer-Nameki
for the pure spinor formulation.Comment: 37 pages; v2: Result on Jacobi identity and Yang-Baxter equation
added in section 3.3; v3: References added; v4: Comparison with ref [12]
clarified in section 3.
Soil characterization in a subtropical forest crossed by highways (Cantareira State Park, SP, Brazil)
Three-Point Functions in N=4 SYM Theory at One-Loop
We analyze the one-loop correction to the three-point function coefficient of
scalar primary operators in N=4 SYM theory. By applying constraints from the
superconformal symmetry, we demonstrate that the type of Feynman diagrams that
contribute depends on the choice of renormalization scheme. In the planar
limit, explicit expressions for the correction are interpreted in terms of the
hamiltonians of the associated integrable closed and open spin chains. This
suggests that at least at one-loop, the planar conformal field theory is
integrable with the anomalous dimensions and OPE coefficients both obtainable
from integrable spin chain calculations. We also connect the planar results
with similar structures found in closed string field theory.Comment: 34 pages, 9 figures, harvmac; references adde
Integrable Open Spin Chains and the Doubling Trick in N = 2 SYM with Fundamental Matter
We demonstrate that the one-loop anomalous dimension matrix in N = 2 SYM with
a single chiral hypermultiplet of fundamental matter, which is dual to AdS_5 X
S^5 with a D7-brane filling AdS_5 and wrapped around an $^3 in the S^5, is an
integrable open spin chain Hamiltonian. We also use the doubling trick to
relate these open spin chains to closed spin chains in pure N = 4 SYM. By using
the AdS/CFT correspondence, we find a relation between the corresponding open
and closed strings that differs from a simple doubling trick by terms that
vanish in the semiclassical limit. We also demonstrate that in some cases the
closed string is simpler and easier to study than the corresponding open
string, and we speculate on the nature of corrections due to the presence of
D-branes that this implies.Comment: 30 pages, 14 figure
Six and seven loop Konishi from Luscher corrections
In the present paper we derive six and seven loop formulas for the anomalous
dimension of the Konishi operator in N=4 SYM from string theory using the
technique of Luscher corrections. We derive analytically the integrand using
the worldsheet S-matrix and evaluate the resulting integral and infinite sum
using a combination of high precision numerical integration and asymptotic
expansion. We use this high precision numerical result to fit the integer
coefficients of zeta values in the final analytical answer. The presented six
and seven loop results can be used as a cross-check with FiNLIE on the string
theory side, or with direct gauge theory computations. The seven loop level is
the theoretical limit of this Luscher approach as at eight loops
double-wrapping corrections will appear.Comment: 18 pages, typos correcte
Yang-Mills Duals for Semiclassical Strings
We consider a semiclassical multiwrapped circular string pulsating on S_5,
whose center of mass has angular momentum J on an S_3 subspace. Using the
AdS/CFT correspondence we argue that the one-loop anomalous dimension of the
dual operator is a simple rational function of J/L, where J is the R-charge and
L is the bare dimension of the operator. We then reproduce this result directly
from a super Yang-Mills computation, where we make use of the integrability of
the one-loop system to set up an integral equation that we solve. We then
verify the results of Frolov and Tseytlin for circular rotating strings with
R-charge assignment (J',J',J). In this case we solve for an integral equation
found in the O(-1) matrix model when J' J.
The latter region starts at J'=L/2 and continues down, but an apparent critical
point is reached at J'=4J. We argue that the critical point is just an artifact
of the Bethe ansatz and that the conserved charges of the underlying integrable
model are analytic for all J' and that the results from the O(-1) model
continue onto the results of the O(+1) model.Comment: 26 Pages, LaTeX; v2 Typos corrected, reference update