Month: March 2020

On April 23 we will have a seminar by

Madalena Lemos (CERN)

Title: Surface defects in four-dimensional superconformal theories and chiral algebras

Abstract:
We study BPS surface defects in 4d superconformal field theories and show how symmetries constrain their anomaly coefficients. Focusing on N=(2,2) surface defects we review the protected subsector captured by a two-dimensional chiral algebra. We study the properties of the defect in this subsector and discuss how to compute the aforementioned anomaly coefficients.

Meeting information:
23rd of April at 14:30 Italian Time
Zoom Meeting https://zoom.us/j/198435430

Slides are available at
https://pandora.infn.it/public/f8ed5f

You can watch the recording at
https://pandora.infn.it/public/e63cae

On April 16 we will have a seminar by

David Tong (Cambridge U.)

Title: A New 5d Non-Supersymmetric Fixed Point?

Abstract: The question mark is important.

Meeting information:
16th of April at 14:30 Italian Time
Zoom Meeting https://zoom.us/j/198435430

Slides are available at
https://pandora.infn.it/public/e46e51

You can watch the recording at
https://pandora.infn.it/public/615f1a

On April 9 we will have a seminar by

Luigi Tizzano (SCGP Stony Brook)

Title: Extremal Correlators and Random Matrix Theory

Abstract:
I will describe how the large charge limit of extremal correlators in N=2 superconformal field theories is captured by a dual description which is a random matrix model of the Wishart-Laguerre type. This gives a new analytic handle on the physics in some particular excited states. The random matrix model also admits a ‘t Hooft expansion in which the matrix is taken to be large and simultaneously the coupling is taken to zero. This explains why the extremal correlators of SU(2) gauge theory obey a nontrivial double scaling limit in states of large charge.

Meeting information:
9th of April at 14:30 Italian Time
Zoom Meeting https://zoom.us/j/198435430

Slides are available at
https://pandora.infn.it/public/52981e

You can watch the recording at
https://pandora.infn.it/public/b393bf

On April 2 we will have a seminar by

Noppadol Mekareeya (INFN Milano Bicocca & Chulangokorn U. Bangkok)

Title: 3d S-fold SCFTs

Abstract:
A local SL(2,Z) transformation on the Type IIB brane configuration gives rise to an interesting class of 3d superconformal field theories, known as the S-fold SCFTs. One of the interesting features of such a theory is that, in general, it does not admit a conventional Lagrangian description. Nevertheless, it can be described by a quiver diagram with a link being a superconformal field theory, known as the T(U(N)) theory. In this talk, we discuss various interesting properties of the S-fold theories, including supersymmetry enhancement in the infrared as well as several interesting dualities.

Meeting information:
2nd of April at 14:30
Zoom Meeting https://zoom.us/j/198435430

Slides are available at
https://pandora.infn.it/public/3c8cc4

You can watch the recording at
https://pandora.infn.it/public/1929ad

On March 26 we will have a seminar by

Massimo Taronna (Napoli U.)

Title: Bootstrapping (A)dS exchanges

Abstract:
Gravitational observables are inherently holographic in nature. When the asymptotic boundary of space time admits a canonical definition of time this allows to use standard principles of Quantum Mechanics to describe such observables. On the other hand the situation is not clear otherwise. This is the case in dS space where the boundary is space-like. Nonetheless bulk causality must be imprinted at the boundary in some way. In this talk I will discuss how to bootstrap tree level amplitudes both in AdS and dS. I will fix from first principles the form of such holographic observables discussing their singularities. In AdS I will also discuss how the knowledge of exchange amplitudes alone allows to derive non-perturbative constraints on CFT correlators writing down extremal functionals for the CFT bootstrap in arbitrary dimensions

Meeting information:
26th of March at 14:30
Zoom Meeting https://zoom.us/j/198435430

Slides are available at
https://pandora.infn.it/public/377a24

You can watch the recording at
https://pandora.infn.it/public/69ae67

On March 19th we will launch the seminar series with a double feature:

Domenico Orlando (INFN Torino)
Introduction to the large charge expansion

Alessandro Sfondrini (Padova University)
Generalised T-Tbar flow equations from scattering factorisation

The meeting will start at 14.30 Italian time.

Slides are available at
https://pandora.infn.it/public/9f8e5f
https://pandora.infn.it/public/d1f459