To account for all the bulk microstates of a three-charge black hole, the supergravity approximation may not suffice and full control over string theory may be essential.

Recently, a specific family of black hole microstates was shown to admit an exact string worldsheet description. The worldsheet theory is a coset of the well-studied AdS$_3 \times \mathbb{S}^3 \times \mathbb{T}^4$ model....

Taking the non-relativistic limit for strings changes the target space geometry, which becomes Newton-Cartan (non-Lorentzian). Therefore the non-relativistic AdS/CFT correspondence would be the first example of non-Lorentzian holography. In this gong-show I will summarise my recent work about understanding the string side of such correspondence.

The double copy (DC) correspondence provides an interesting relation between gravity and gauge theories. Strongly supported in the context of amplitudes, its Lagrangian counterpart has been partially investigated, for which the DC field is described through a convolution. Using this definition, we explore the possibility of extending the correspondence to asymptotic symmetries for the N=0...

In the past two years there has been a surge in the interest towards low dimensional gauged supergravity solutions where the spacetime metric includes a $2\text{d}$ orbifold known as spindle. Topologically a spindle is a 2-sphere, but it has conical singularities at the two poles. Remarkably, uplifting such solutions to type IIB/$11\text{d}$ supergravity on Sasaki-Einstein manifolds leads to...

Scattering from conformal interfaces in two dimensions is universal, since the flux of transmitted and reflected energies does not depend on the details of the initial state.

Previous studies of the transmission coefficient either involved a minimal holographic model with a single thin brane inside three-dimensional AdS, or a double brane model involving the merging of two branes.

In this...

Higher-form symmetries provide a powerful way to constrain the non-perturbative data of a quantum field theory. This is especially valuable in the case of d > 4 superconformal field theories since all known examples are intrinsically strongly coupled. In my short presentation, I will provide two different approaches to the computation of the Defect Group, the symmetry group acting on defects,...

In recent years a lot of attention has been paid to generalized notions of global symmetries in QFT, and their consequences for the dynamics. In particular, symmetries whose underlying mathematical structure is not described by group theory but by category theory, the so-called non-invertible symmetries, have been discovered to exist also in 4d gauge theories. This raises the important...

The last few years have witnessed a paradigm shift concerning the concept of symmetry in QFT, with the focus passing from the action on fields in the Lagrangian to the presence in the theory of special extended operators with the remarkable property of depending only topologically on their support. This led to a broader notion of what we call symmetry in QFT, which encompasses apparently...

We build an asymptotic symmetry algebra for massless higher-spin fields in asymptotically Minkowski space-time in any space-time dimension. It is constructed at null infinity from the (electric) conformal Carrollian scalar which can be interpreted as the flat-space limit of the singleton representation of the conformal algebra.

Orientifold projections are an important ingredient in geometrical engineering of Quantum Field Theory. However, an orientifold can break down the superconformal symmetry and no new superconformal fixed points are admitted (II scenario); nevertheless, in some cases, dubbed I and III scenarios orientifold, a new IR fixed point is achieved and, for III scenario examples, some still not fully...

I will discuss recent developments in the study of 3-point functions of chiral single-trace scalar operators in a four-dimensional N=2 superconformal quiver theory with gauge group SU(N)×SU(N) and bifundamental matter. Using supersymmetric localization, it is possible to map the computation of these correlators to an interacting matrix model and obtain expressions that are valid for any value...

I describe novel supersymmetric configurations with line and local operators in 3d theories with N ≥ 4 supersymmetry and explain how to extract defect CFT data using localization. As an application, I will compute defect correlators of the stress tensor multiplet in ABJM with the 1/2-BPS Wilson line.

In this talk, I will begin with a review of the known vacua for ten-dimensional non-supersymmetric strings, with and without (R-R or gauge) fluxes, focusing on their stability properties.

Following a recent attempt to define a notion of energy in string compactifications, I will present a Nester-Witten energy for vacua without fluxes. Among these, the Dudas-Mourad vacua, known to be...

In quantum field theory, an orbifold is a way to obtain a new theory from an old one by gauging a finite global symmetry. This definition of orbifold does not make sense for quantum gravity theories, that admit (conjecturally) no global symmetries. In string theory, orbifold refers to the gauging of a

global symmetry on the world-sheet theory describing the fundamental string. Alternatively,...

We study the cosmological evolution of string compactifications where the volume modulus has a non-trivial time dependence. Our main result will be to show how a kinating volume modulus in 4 spacetime dimensions can be uplifted to a classical Kasner solution in 10 d. Within a classical picture, this implies that if the kinetic energy of the rolling scalar were enough to overcome the potential...