7 research outputs found
An integrable deformation of the AdS5×S5superstring
The S-matrix on the world-sheet theory of the string in AdS5 x S5 has
previously been shown to admit a deformation where the symmetry algebra is
replaced by the associated quantum group. The case where q is real has been
identified as a particular deformation of the Green-Schwarz sigma model. An
interpretation of the case with q a root of unity has, until now, been lacking.
We show that the Green-Schwarz sigma model admits a discrete deformation which
can be viewed as a rather simple deformation of the F/F_V gauged WZW model,
where F=PSU(2,2|4). The deformation parameter q is then a k-th root of unity
where k is the level. The deformed theory has the same equations-of-motion as
the Green-Schwarz sigma model but has a different symplectic structure. We show
that the resulting theory is integrable and has just the right amount of
kappa-symmetries that appear as a remnant of the fermionic part of the original
gauge symmetry. This points to the existence of a fully consistent deformed
string background.Comment: 23 pages, improved and expanded discussion of metric and B fiel
The structure of non-abelian kinks
We consider a class of integrable quantum field theories in 1+1 dimensions
whose classical equations have kink solutions with internal collective
coordinates that transform under a non-abelian symmetry group. These
generalised sine-Gordon theories have been shown to be related to the world
sheet theory of the string in the AdS/CFT correspondence. We provide a careful
analysis of the boundary conditions at spatial infinity complicated by the fact
that they are defined by actions with a WZ term. We go on to describe the local
and non-local charges carried by the kinks and end by showing that their
structure is perfectly consistent with the exact factorizable S-matrices that
have been proposed to describe these theories.Comment: 41 pages, more typos correcte
The Quantum Affine Origin of the AdS/CFT Secret Symmetry
We find a new quantum affine symmetry of the S-matrix of the one-dimensional
Hubbard chain. We show that this symmetry originates from the quantum affine
superalgebra U_q(gl(2|2)), and in the rational limit exactly reproduces the
secret symmetry of the AdS/CFT worldsheet S-matrix.Comment: 22 page
One-loop corrections to AdS_5 x S^5 superstring partition function via Pohlmeyer reduction
We discuss semiclassical expansions around a class of classical string
configurations lying in AdS_3 x S^1 using the Pohlmeyer-reduced from of the
AdS_5 x S^5 superstring theory. The Pohlmeyer reduction of the AdS_5 x S^5
superstring theory is a gauged Wess-Zumino-Witten model with an integrable
potential and two-dimensional fermionic fields. It was recently conjectured
that the quantum string partition function is equal to the quantum reduced
theory partition function. Continuing the previous paper (arXiv:0906.3800)
where arbitrary solutions in AdS_2 x S^2 and homogeneous solutions were
considered, we provide explicit demonstration of this conjecture at the
one-loop level for several string solutions in AdS_3 x S^1 embedded into AdS_5
x S^5. Quadratic fluctuations derived in the reduced theory for inhomogeneous
strings are equivalent to respective fluctuations found from the Nambu action
in the original string theory. We also show the equivalence of fluctuation
frequencies for homogeneous strings with both the orbital momentum and the
winding on a big circle of S^5.Comment: 45 pages, references added, minor correction
Coideal Quantum Affine Algebra and Boundary Scattering of the Deformed Hubbard Chain
We consider boundary scattering for a semi-infinite one-dimensional deformed
Hubbard chain with boundary conditions of the same type as for the Y=0 giant
graviton in the AdS/CFT correspondence. We show that the recently constructed
quantum affine algebra of the deformed Hubbard chain has a coideal subalgebra
which is consistent with the reflection (boundary Yang-Baxter) equation. We
derive the corresponding reflection matrix and furthermore show that the
aforementioned algebra in the rational limit specializes to the (generalized)
twisted Yangian of the Y=0 giant graviton.Comment: 21 page. v2: minor correction