Doubly holographic braneworld models played an important role in understanding the role of entanglement islands. They offer three complementary perspectives: the usual AdS bulk and boundary CFT descriptions, but also a brane picture where a gravitational theory is coupled to a CFT. I will discuss ongoing work on the study of entanglement entropy in a model of braneworld evaporation. From the...
We review recent developments concerning the properties of de Sitter vacua of 4D supergravity. In particular, we analyze the consistency the de Sitter vacua within 4D gauged supergravity from the perspective of the swampland, focusing on the implications of the magnetic weak gravity conjecture, and we also briefly discuss recent developments related to anti-brane uplifts and non-linear supersymmetry.
The embedding of accelerated expansion, in particular our past and present cosmology, in string theory remains an open problem in string phenomenology. Certain swampland conjectures place stringent bounds on such models. In this talk I will focus on multifield quintessence in the late universe, and the search for transients close to the cosmological parameters today. I will conclude that...
In this talk, I discuss some examples of UV-free chiral gauge theories, looking at their IR effective descriptions from the point of view of symmetries and anomalies. In particular, I show how the 't Hooft anomaly matching conditions (generalized by including higher form symmetries) and the realization of symmetries (either broken or unbroken, exacts or anomalous) allow us to learn some...
In this talk I will illustrate recent progress on the connection between scattering amplitudes and the classical emission of gravitational waves in black-hole scattering events. Focusing on the eikonal exponentiation, which provides a strategy to extract the classical limit, I will describe how amplitudes determine the classical deflection in the black-hole trajectories and the spectra of...
Reversing the logic of the bootstrap approach in Liouville CFT we explicitly compute the connection formulae for degenerate conformal blocks. In the semiclassical limit of the theory, this amounts to solving the connection problem of Fuchsian ODEs. Generalizing to irregular insertions we solve as well for various confluences of the ODE. Concentrating on the Heun equation and its confluences,...
In 1977 Blandford & Znajek (BZ) initiated the analytic study of force-free magnetospheres by developing a perturbation scheme in the slow spin regime of a Kerr black hole, which lead to the discovery of a viable electromagnetic Penrose-like process for extracting energy and angular momentum. In this talk we solve the BZ perturbation theory at higher orders by means of a matched asymptotic...
In this talk, I will discuss the TTbar deformation of Yang-Mills theory in two dimensions. Focusing on the sphere topology and unitary gauge groups, I will show how the deformed partition function can be obtained by solving the relevant flow equation at the level of individual flux sectors. For positive values of the deformation parameter, the quantum spectrum of the theory experiences a...
In this talk I will discuss IR dualities for 3d supersymmetric QCD with
four supercharges and extra fields in tensorial representation of the
gauge group, giving rise to superpotential of D-type, where D refers to
the A-D-E classification. The prototypical example of such dualities was conjectured in the mid 90's for SU(N) SQCD with four supercharges and with two adjoints. Various...
We consider the N=2 SYM theory with gauge group SU(N) and a matter content consisting of one multiplet in the symmetric and one in the anti-symmetric representation of the gauge group. This theory is conformal and it admits a large-N 't Hoof t expansion and a gravity dual given by a particular orientifold of AdS_5 X S^5. We analyze this theory relying on
the matrix model provided by...
I will explain how in the expansion near roots of unity, the four-dimensional superconformal index decomposes into a sum over independent sectors, some of them described by A-models wrapping Riemann surfaces. Starting from the four dimensional index the partition function of these lower dimensional systems is reduced to a sum over vacua of the specific A-model. The number of degrees of freedom...
Supersymmetric field theories represent an invaluable theoretical laboratory for the exploration of non-perturbative dynamics and their geometric realization in string theory has proven to be a very effective tool to understand them, allowing us to construct and study in detail the properties of strongly-coupled theories even when they lack a lagrangian description. In this talk I will present...
We discuss special subsectors of protected operators appearing in quantum field theories with extended supersymmetry defined on a general class of three-dimensional manifolds. Correlators of such BPS operators are generated by a one-dimensional Gaussian model obtained from localization and turn out to be topological as well as strongly dependent on the global features of the original...
The brane tiling machinery allows us to construct 4d SCFTs that represent the gauge side of the AdS/CFT correspondence. These theories arise from D3 branes probing a singular toric CY cone. One can add orientifold planes to the system, and the projected gauge theory can still be read from the brane tiling. One may expect that either the orientifold yields subleading correction to R-charges and...
In this talk I will explain first of all a new connection we found between quantum integrable models and black holes' perturbation theory. To begin with, I will introduce black holes’ quasinormal modes (QNMs) and their role in gravitational waves observations, showing in particular how to connect their mathematically precise definition with the integrable model's (IM) structures derived from...
Orbifolding in string theory is a standard procedure to get new theories from old ones either by gauging a global symmetry of the worldsheet sigma model or by quotienting a geometric string background by some isometries. The absence of global symmetries characterizes all known string theory models (and, conjecturally, all theories of quantum gravity), so that the orbifold procedure from a...
The main features of the Jacobi sigma model will be illustrated. The Jacobi sigma model is a topological field theory with target space a Jacobi manifold, and it is a generalization of the Poisson sigma model. It is a non-linear gauge theory and it has interesting properties which can be useful for both physical and mathematical applications. In particular, contact as well as locally conformal...
