In this talk I will discuss recent developments in the study of Wilson loop correlators in four-dimensional \mathcal{N} = 2 superconformal gauge theories. Using supersymmetric localization, it is possible to map the computation of these observables to an interacting matrix model and obtain expressions for these correlators in terms of Fredholm determinants of a Bessel operator, that are valid...
Since the first discovery of gravitational waves resulting from a binary black hole coalescence, the study of the post-merger phase, known as ringdown, has proven to be one of the most promising tools for testing gravity and exploring fascinating extensions of general relativity. In this talk I will discuss one of these extensions, called Einstein-Maxwell-scalar theory, where a scalar field is...
We approach the problem of open-closed duality through the complete perspective of string field theory (SFT) and we provide a description of the backreaction of a large N stack of D-branes as a new closed string background without D-branes. To achieve this, we first of all give a new convenient formulation of open-closed SFT based on a single open-closed nilpotent structure which captures the...
I will discuss the computation of correlators and observable quantities, in particular OPE coefficients, in Argyres-Douglas theories, that are 4-dimensional N = 2 superconformal field theories, intrinsically strongly coupled and without a Lagrangian description. After a quick presentation on these theories and the motivation of this study, I will recall some results for extremal correlators...
"Extended operators such as defects are of fundamental importance in conformal field theories, with applications both in high energy theory and in condensed matter systems at criticality. Recently, analytic bootstrap techniques have been successfully applied to study these objects.
In this talk we will focus on the O(3) magnetic impurity, which at the fixed point is described by a defect...
Within the framework of recovering general relativity from scattering amplitudes, it is possible to compute the metric induced by the most generic rotating spherically-symmetric matter configuration at quadrupole order by considering stationary massive spin-1 particles emitting gravitons. This approach leads to a natural definition of a multipole expansion in any dimension and the observation...
DDF operators/states was a formalism first developed by Di Vecchia, Del Giudice and Fubini around 1972. It gives an explicit construction of BRST invariant, not exact (bosonic) string states which I shall briefly recap in the introduction. It is very useful for studying massive string spectra and their scattering amplitudes. After the introduction, the talk will focus on generalising the...
We consider linear scalar perturbartions of JMaRT geometries in type IIB supergravity beyond the near-decoupling limit. In addition to confirm that these solutions suffers of instability for the presence of an ergoregion without horizon, we also find quasi-normal modes (QNMs) with positive imaginary part that can be interpreted in terms of the emission of charged (scalar) quanta with non zero...
Topological stars are smooth horizonless static solutions of Einstein-Maxwell theory in 5-d and they represent possible microstate geometries for non-supersymmetric black holes. They have been proved to be (linearly) stable by studying their spectrum of chargeless quasi-normal modes; their deformability has been analysed through the Tidal Love Number both in the static and the dynamical case....
