Triangle Seminars
Wednesday, 28 Nov 2018
The Cross Anomalous dimension in N=4 super Yang–Mills
📍 London
Hagen Munkler
(ETH Zurich)
Abstract:
The cross or soft anomalous dimension matrix describes the
renormalization of Wilson loops with a self-intersection
and is an important object in the study of infrared divergences of
scattering amplitudes. I will discuss it for the
case of the Maldacena–Wilson loop in N=4 supersymmetric Yang–Mills
theory, considering both the strong-coupling
description in terms of minimal surfaces in AdS5 as well as the
weak-coupling side up to the two-loop level. In
either case, the coefficients of the cross anomalous dimension matrix
can be expressed in terms of the cusp anomalous
dimension. The strong-coupling description displays a Gross–Ooguri
phase transition and I will argue that the cross
anomalous dimension is an interesting object to study in an
integrability-based approach.
The cross or soft anomalous dimension matrix describes the
renormalization of Wilson loops with a self-intersection
and is an important object in the study of infrared divergences of
scattering amplitudes. I will discuss it for the
case of the Maldacena–Wilson loop in N=4 supersymmetric Yang–Mills
theory, considering both the strong-coupling
description in terms of minimal surfaces in AdS5 as well as the
weak-coupling side up to the two-loop level. In
either case, the coefficients of the cross anomalous dimension matrix
can be expressed in terms of the cusp anomalous
dimension. The strong-coupling description displays a Gross–Ooguri
phase transition and I will argue that the cross
anomalous dimension is an interesting object to study in an
integrability-based approach.
Posted by: KCL
Reconstructing AdS3/CFT2 correlators
Rodolfo Russo
(QMUL)
Abstract:
The AdS/CFT duality maps supersymmetric heavy operators with
conformal dimension of the order of the central charge to asymptotically
AdS supergravity solutions. I'll show how, by studying the quadratic
fluctuations around such backgrounds, it is possible to derive 4-point
correlators of two light and two heavy states in the supergravity
approximation. Then by using this input, I'll discuss how to reconstruct
standard supergravity correlators between four (single particle)
operators. I'll present some explicit examples in the AdS3 setup relevant
for the duality with the D1-D5 CFT.
The AdS/CFT duality maps supersymmetric heavy operators with
conformal dimension of the order of the central charge to asymptotically
AdS supergravity solutions. I'll show how, by studying the quadratic
fluctuations around such backgrounds, it is possible to derive 4-point
correlators of two light and two heavy states in the supergravity
approximation. Then by using this input, I'll discuss how to reconstruct
standard supergravity correlators between four (single particle)
operators. I'll present some explicit examples in the AdS3 setup relevant
for the duality with the D1-D5 CFT.
Posted by: IC
Thursday, 29 Nov 2018
Walking, weakly first order phase transitions and complex CFTs
Bernardo Zan
(EPFL Lausanne)
Abstract:
I will discuss walking behavior in gauge theories and weakly first order phase transition in statistical models. Despite being phenomena appearing in very different physical systems, they both show a region of approximate scale invariance. They can be understood as a RG flow passing between two fixed points living at complex couplings, which we call complex CFTs. By using conformal perturbation theory, knowing the conformal data of the complex CFTs allows us to make predictions on the observables of the walking theory. As an example, I will discuss the two dimensional Q-state Potts model with Q>4.
I will discuss walking behavior in gauge theories and weakly first order phase transition in statistical models. Despite being phenomena appearing in very different physical systems, they both show a region of approximate scale invariance. They can be understood as a RG flow passing between two fixed points living at complex couplings, which we call complex CFTs. By using conformal perturbation theory, knowing the conformal data of the complex CFTs allows us to make predictions on the observables of the walking theory. As an example, I will discuss the two dimensional Q-state Potts model with Q>4.
Posted by: QMW