Asymptotically-flat spacetimes play a central role in the study of gravitational radiation. They are also the arena which enables to understand the relationship between asymptotic symmetries, soft graviton theorems, and memory effects. While this relationship is well understood at leading order in terms of BMS symmetries and flux-balance laws for the mass and angular momentum, the subleading structure has only begun to be investigated recently. In this talk we will present a study of this subleading structure using the Newman-Penrose formalism. This enables to identify an infinite tower of quasi-conserved charges generating an intriguing algebraic structure.

Recent progress has provided methods to compute and match finite N (supersymmetric) partition functions on both sides of the holographic duality within string and M-theory. An advent that allows for interesting opportunities in the study of quantized strings and branes in curved backgrounds. I will discuss \mathcal{N}=4 SYM, its S-fold cousins, and how localization allows to compute their supersymmetric partition functions analytically as a function of N. We will subsequently discuss some peculiar features of these S-folds; such as their seemingly non-compact conformal manifold, and the fact that their partition functions can be expanded in fluctuating gravitons and D3-branes, very much a-like the giant graviton expansion in \mathcal{N}=4 SYM, even though a clear index interpretation is absent on the QFT side.

Detecting local Non-Gaussianity provides valuable insights into the early universe's particle composition. Interactions between the inflaton and light particles yield distinctive signatures, potentially observable in upcoming surveys. However, addressing IR divergences in light fields on de Sitter spacetimes requires careful treatment. Stochastic inflation offers a solution, but its relationship with perturbative computations remains unclear. In this presentation, we establish a precise connection between perturbation theory and stochastic formalism using the wavefunction formalism. We extend this analysis to multifield inflation models and clarify recent non-perturbative findings from stochastic inflation through their compatibility with perturbation theory calculations.

I will present a method for deriving the microscopic entropy of a very general class of supersymmetric, rotating, and accelerating black holes in AdS(4). This is achieved by analyzing the large-N limit of the spindle index.

Topological orders in 2+1 dimensions are captured by modular tensor categories (MTCs). We propose a correspondence that assigns a fusion category to a pair (M,G), where M is a Seifert 3-manifold and G is an ADE Lie group. We conjecture that the fusion category associated to (M,G) is an MTC if and only if M has trivial first homology group with coefficients in the center of G. The construction determines the spins of anyons and their S-matrix, and provides a constructive way to access the R- and F-symbols from simple building blocks. We explore the possibility that this correspondence provides an alternative classification of MTCs, which is put to the test by realizing all MTCs (unitary or non-unitary) with rank at most 5.

We describe a powerful new technique for computing various physical observables in supergravity, without solving any supergravity equations. Applications include gravitational free energies, black hole entropies, and central charges and other CFT quantities of interest in holography. In the talk I will aim to describe the general idea, and give a flavour of some applications.

I will review the theoretical and experimental status in the search of primordial non-Gaussianity, focussing on some recent developments and ideas. In particular I will try to answer the question: what are we going to learn when experiments will be able to probe f_NL ~ 1?

Previous work has given proof and evidence that BPS states in local Calabi-Yau 3-folds can be described and counted by exponential networks on the punctured plane, with the help of a suitable non-abelianization map to the mirror curve. This provides an appealing elementary depiction of moduli of special Lagrangian submanifolds, but so far only a handful of examples have been successfully worked out in detail. In this talk, I will present an explicit correspondence between torus fixed points of the Hilbert scheme of points on ℂ^2⊂ℂ^3 and anomaly free exponential networks attached to the quadratically framed pair of pants. This description realizes an interesting, and seemingly novel, “age decomposition” of linear partitions. We also provide further details about the networks’ perspective on the full D-brane moduli space.

Diverse observations have established the standard cosmological model, known as $\Lambda CDM$. Within this model, the Universe began in a hot dense state filled with tiny primordial density fluctuations. These fluctuations grew as they collapsed under gravity and eventually became the seeds of the galaxies throughout the Universe. A key question is where did these initial perturbations come from? The leading model for their creation, known as inflation, posits that these arose from quantum vacuum fluctuations that were stretched to cosmic scales by a period of exponential expansion of the Universe. Many models predict that this process will leave distinct statistical signatures on the primordial density perturbations. In this talk I will discuss how we can use the spatial distribution of galaxies to search for these early Universe signatures. In particular, I will show how novel analysis methods will allow us to robustly disentangle the primordial information from late-time physics. These approaches will shed new light on aspects from the number of fields present during inflation to the strength of interactions to symmetries of inflation.

I will describe a surprisingly simple representation of a class of integrated correlation functions of four superconformal primaries in the stress tensor multiplet of N=4 supersymmetric Yang-Mills theory with arbitrary simple gauge group, G. I then present exact formulae for these integrated correlators which are manifestly invariant under GNO electro-magnetic duality. For classical gauge groups, G=SU(N), SO(N), USp(2N), In the large-N limit these correlators are interpreted via holography in terms of the low-energy expansion of type IIB superstring amplitudes in AdS_5XS^5 or an orientifold thereof. In this way I recover the SL(2,Z)-invariant BPS interactions, arising in type IIB superstring amplitudes in the flat-space limit. From the asymptotic nature of the 1/N expansion I furthermore reconstruct non-perturbative contributions which holographically correspond to (p,q)-string world-sheet instantons.

QFT at finite temperature can be studied via compactifying the time direction. Placing CFTs on this non-trivial manifold, a subgroup of conformal symmetries is broken. Nonetheless, it is possible to derive broken Ward identities, which provide novel constraints on the theory. These constraints not only systematically reproduce all known results, including an implicit formulation of the generalized Cardy formula, but also relate the thermal energy spectrum with the conformal spectrum. Moreover, novel sum rules for one-point functions of operators are derived. They allow the computation of one-point functions for light operators in terms of zero temperature data, as well as their asymptotic behavior for heavy operators.

It is natural to expect that quantum gravity is not directly relevant at the low energies which experimentally accesible today, since the Planck scale is many orders of magnitude above the electroweak scale. However, mounting evidence coming from String Theory compactifications, general considerations based on black hole evaporation and holography suggest that there are some constraints that must be satisfied by low-energy effective field theories coupled to Einsteinian gravity. These constraints can in principle be used to rule out models at low energies or to connect with observations, an effort dubbed the "Swampland Program". I will review the program, its motivation, and recent advances.

The Symmetry TFT of a quantum field theory is a Topological Field Theory in one dimension more, that describes the structure of the symmetry, its representations, its anomalies, and the possible topological manipulations (gaugings). Until recently only the case of finite symmetries had been addressed. I will present a proposal for the Symmetry TFT of theories with a U(1) symmetry: it is a BF theory with a continuum of topological operators. I will discuss many examples, including chiral anomalies, 2-groups, the non-invertible Q/Z chiral symmetry in 4d with ABJ anomaly, and I will discuss the non-Abelian case as well.

In this talk, we examine a fundamental question posed some time ago by Birkhoff and von Neumann: What are the possible structures of measurement in a theory of Physics? We find striking connections with the conceptual framework of First Order Logic, and apply classification theorems for the automorphism groups of first order relational structures to argue for the uniqueness of Hilbert space as the phase space of a theory with probabilistic transitions between atomic states. We discuss possible applications of these observations to Algebraic Quantum Field Theory.

Recently there has been a renewed interest in the subject of novel types of symmetries, now known as generalized symmetries. An interesting question is what happens to these more general symmetry structures upon compactification to lower dimensions. In this talk, we shall explore this in the context of the compactification of 4d N=1 SCFTs to 2d on spheres.

I will present a constructive method to compute the Virasoro-Shapiro amplitude on AdS5xS5, order by order in AdS curvature corrections. The k-th curvature correction takes the form of a genus zero world-sheet integral involving single-valued multiple polylogarithms of weight 3k. The coefficients in an ansatz in terms of these functions are fixed by Regge boundedness of the amplitude, which is imposed via a dispersion relation in the holographically dual CFT. We explicitly constructed the first two curvature corrections. Our final answer reproduces all CFT data available from integrability and all localisation results, to this order, and produces a wealth of new CFT data for planar N=4 SYM theory at strong coupling. Finally, the high energy limit of the AdS Virasoro-Shapiro amplitude is compared to a classical scattering computation in AdS and agreement is found.

I’ll give a pedagogical introduction to some conceptual aspects of quantum materials in and out of equilibrium. Such materials, capable of realising exotic states of matter, hold promise for manifold applications in areas like microelectronics and quantum computing. The most basic quantum materials are electronic band insulators. My talk will start with an explanation of how they can be categorised based on crystalline symmetry and topology. Following this, I will broaden the framework of band topology to include non-Hermitian Hamiltonians, which describe systems that are not in equilibrium. To conclude my talk, I will delve into a curious connection between Hermitian bulk and non-Hermitian boundary topological invariants.

Abstract: On general grounds, the spectrum of a Conformal Field Theory (CFT) is expected to be extremely complicated away from special limits. One of such limits consists of the lowest energy states for every given spin, which are also known as the leading-twist states. In this talk I will discuss the structures that emerge in the spectrum as one departs from this limit towards the higher-twist states, focusing especially on the Regge trajectories. In particular, I will describe a general mechanism that reconciles the idea of Regge trajectories with the growing number of local operators at large spin. I will then demonstrate how this mechanism works in the case of one-loop phi^4 Wilson-Fisher theory in epsilon-expansion. This example will also clarify the properties of double-twist trajectories and light-cone bootstrap at higher-twist. Finally, I will briefly discuss a work in progress on going beyond the double-twist limit.

In this talk, we delve into the world of spindle and disc solutions dual to 4d SCFTs. Despite extensive studies conducted over the years, certain aspects continue to challenge our understanding. Disc solutions, conjectured to be dual to Argyres-Douglas theories, present a puzzle as at first sight the symmetries do not match across the holographic correspondence. The spindle solutions, on the other hand, completely lack a proper understanding of their dual field theories. This talk aims to shed light on these puzzles, offering a detailed explanation for the breaking of the unwanted symmetry in disc solution. Furthermore, we will clarify various aspects of the spindle solution, contributing to a more profound understanding of the class S origin of the dual SCFTs. As a byproduct, we enlarge the class of holographic surface defects of the (2,0) theory as well as provide a concrete description of a class of locally N=1 preserving punctures.