Vacua of different gaugings of $D = 4$ $\mathcal{N} = 8$ supergravity that preserve the same supersymmetries and bosonic symmetry tend to exhibit the same universal mass spectrum within their respective supergravities. For AdS${}_4$ vacua in gauged supergravities that arise upon consistent truncation of string/M-theory, we will show in this talk that this universality is lost at higher...
We argue that nonperturbative CFT correlation functions admit Mellin amplitude representation. Perturbative Mellin representation readily follows. We derive main properties of nonperturbative CFT Mellin amplitudes: analyticity, unitarity and polynomial boundedness at infinity. We consider dispersion relations for Mellin amplitudes and use them to derive bootstrap bounds and constrain AdS...
We study limits of infinite distance in the moduli space of 4d N = 2 string compact- ifications, in which instanton effects dominate. We first consider trajectories in the hypermultiplet moduli space of type IIB Calabi-Yau compactifications. We observe a correspondence between towers of D-brane instantons and D-brane 4d strings, such that the lighter the string the more relevant the instanton...
Following the paper called Discrete Symmetries in Dimer Diagrams ( https://arxiv.org/abs/1907.06938 ), we apply dimer diagram techniques to uncover discrete global symmetries in the fields theories on D3-branes at singularities given by general orbifolds of general toric Calabi-Yau threefold singularities. The discrete symmetries are discrete Heisenberg groups, with two generators A,B with...
Notions of operator complexity characterize how fast information scrambles in a many body quantum system. For holographic systems, it has recently been conjectured that the 'size' of an operator can be interpreted in terms of the mechanical momentum of an effective particle in the bulk. In this talk, I will first introduce a different notion of operator complexity for holographic systems by...
Plasma balls are dropplets of deconfined plasma surrounded by a confining vacuum. We present the first holographic simulation of their real-time dynamics via the dynamics of localised, finite-energy black holes in the AdS soliton background. We consider horizonless initial data sourced by a massless scalar field. Upon time evolution, prompt scalar field collapse produces an excited black hole that...
The leading order low-energy effective action of string theory is symmetric under T-duality transformations, and although these are such that geometric properties of solutions may change substantially, they still preserve the Hawking temperature and entropy of black holes. The question naturally arises whether this fact holds when one includes higher-order corrections. In this work we present...
New solutions of Einsteinian cubic gravity coupled to a Maxwell field that describe the near-horizon geometry of charged and rotating black holes are presented. We show that the AdS$_2\times\mathbb{S}^2$ near-horizon geometry of Reissner-Nordstr\"om black holes receives no corrections, but deviations with respect to the extremal Kerr-Newman solution appear as we turn on the angular momentum....
We use holography to study the complete set of inhomogenous static solutions of a four-dimensional gauge theory with a first order thermal phase transition. We numerically solve Einstein’s equations using both static and dynamical methods, finding perfect agreement between the results. We analyze their thermodynamic properties and study their local stability, finding unstable solutions. For...
The proposal for a new Swampland conjecture forbidding stable non-supersymmetric "locally AdS" warped throats, which generalizes the Swampland criterion forbidding stable non-supersymmetric AdS vacua, is discussed. The conjecture is motivated by the properties of systems of fractional D3-branes at singularities, and can be used to rule out large classes of warped throats with supersymmetry...
We show some results concerning the holographic entanglement entropy of deformed entangling regions in three-dimensional CFTs dual to Einstein-AdS gravity, using the extrinsic counterterms renormalization scheme. In this prescription, valid for arbitrary dimension, entanglement entropy is given by the sum of a topological term and a geometrical part that explicitly describes the deformation of...
I review aspects of quantum complexity and its holographic counterpart, applied to operator growth in chaotic systems. At time scales longer than the scrambling time, the size of the operator ceases to be a good characterization of its complexity growth. I will show that a new notion of operator complexity, called Krylov-complexity, satisfies the expected linear growth at long times as a...
Generalized quasi-topological gravities (GQTGs) are higher-curvature extensions of Einstein gravity characterized by the existence of non-hairy generalizations of the Schwarzschild black hole which satisfy g_{tt} g_{rr} = −1, as well as for having second-order linearized equations around maximally symmetric backgrounds. In this talk I will provide strong evidence that any gravitational...
I will talk about a recent paper JHEP 1905 (2019) 189, where we compute the most general leading-order correction to the Kerr solution when the Einstein-Hilbert action is supplemented with higher-derivative terms, including the possibility of dynamical couplings controlled by scalars. The model we present depends on five parameters and it contains, as particular cases,...
