Related papers: Operator Products in the SU($\infty$) Principal Ch…
Exact expressions for correlation functions are known for the large-$N$ (planar) limit of the $(1+1)$-dimensional ${\rm SU}(N)\times {\rm SU}(N)$ principal chiral sigma model. These were obtained with the form-factor bootstrap, an entirely…
We report the explicit solution for the vacuum state of the two-dimensional $SU(N)$ Principal Chiral Model at large-$N$ for an arbitrary set of chemical potentials and any interaction strength, a unique result of such kind for an…
We present results for the large-$N$ limit of the (1+1)-dimensional principal chiral sigma model. This is an asymptotically-free $N\times N$ matrix-valued field with massive excitations. All the form factors and the exact correlation…
We obtain exact matrix elements of physical operators of the (1+1)-dimensional nonlinear sigma model of an SU(N)-valued bare field, in the 't Hooft limit N goes to infinity. Specifically, all the form factors of the Noether current and the…
The space of local operators in the SU(2) invariant Thirring model (SU(2) ITM) is studied by the form factor bootstrap method. By constructing sets of form factors explicitly we define a susbspace of operators which has the same character…
We analyze the large $N$ spectrum of chiral primary operators of three dimensional fixed points of the renormalization group. Using the space-time picture of the fixed points and the correspondence between anti-de Sitter compactifications…
It is established by numerical means that the continuum large N principal chiral model in two dimensions has a phase transition in a smoothed two point function at a critical distance of the order of the correlation length.
We study the sigma model with $SU(N)\times SU(N)$ symmetry in 1+1 dimensions. The two- and four-particle form factors of the Noether current operators are found, by combining the integrable-bootstrap method with the large-$N$ expansion.
Decoupling the chiral dynamics in the canonical approach to the WZNW model requires an extended phase space that includes left and right monodromy variables. Earlier work on the subject, which traced back the quantum qroup symmetry of the…
We develop techniques to study the correlation functions of "large operators" whose bare dimension grows parametrically with N, in SO(N) gauge theory. We build the operators from a single complex matrix. For these operators, the large N…
We investigate the high energy behavior of the SU(N) chiral Gross-Neveu model in 1 + 1 dimensions. The model is integrable and matrix elements of several local operators (form factors) are known exactly. The form factors show rapidity space…
The operator product expansion in four-dimensional superconformal field theory is discussed. The OPE takes a particularly simple form for chiral operators, in $N=1$ and $N=2$, and for analytic operators, in $N=2$ and $N=4$. It is argued…
We discuss recent results on two-point functions of chiral primary operators in {\cal N}=4 SU(N) supersymmetric Yang-Mills theory. Our results give further support to the belief that such correlators are not renormalized to all orders in g…
We study two-point correlation functions of chiral/anti-chiral operators in SU(N) $\mathcal{N}=2$ gauge theories with massless hyper-multiplets in a representation $\mathcal{R}$ associated with a non-vanishing $\beta$-function. Using…
Chiral primary operators annihilated by a quarter of the supercharges are constructed in the four dimensional N=4 Super-Yang-Mills theory with gauge group SU(N). These quarter-BPS operators share many non-renormalization properties with the…
We study certain higher-spin chiral operators in N=2 superconformal field theories (SCFTs). In Lagrangian theories, or in theories related to Lagrangian theories by generalized Argyres-Seiberg-Gaiotto duality ("type A" theories in our…
Two-dimensional field theories do not have a moduli space of vacua. Instead, it is common that their low-energy behavior is a sigma model with a target space. When this target space is compact its renormalization group flow is standard.…
We provide a non-renormalization theorem for the coefficients of the conformal anomaly associated with operators with vanishing anomalous dimensions. Such operators include conserved currents and chiral operators in superconformal field…
We study Yang Mills theory in 2+1 dimensions, as an array of coupled (1+1)-dimensional principal chiral sigma models. This can be understood as an anisotropic limit where one of the space-time dimensions is discrete and the others are…
Certain two and three point functions of gauge invariant primary operators of ${\cal N}=4$ SYM are computed in ${\cal N}=1$ superspace keeping all the $\th$-components. This allows one to read off many component descendent correlators. Our…