Review talk n.1

• Alexander Zhiboedov (CERN)

Lagrange-EOB dynamics: a new route from post-Minkowskian theory to waveform models

• Andrea Placidi (University of Perugia)

In this talk, I will present a new formulation of the effective-one-body (EOB) dynamics, particularly well suited for incorporating post-Minkowskian information into waveform models for compact binaries. This is especially timely, as several groups worldwide are currently working to derive increasingly accurate post-Minkowskian results for the two-body problem. After motivating the shift in perspective introduced by our approach, I will discuss its main features and show how, through the crucial use of a Lagrange multiplier in the EOB action, it leads to new EOB equations of motion in Euler–Lagrange form. Finally, I will illustrate the performance of an EOB model based on this new Lagrange-EOB dynamics, which combines post-Newtonian and post-Minkowskian information, and I will mention recent developments for neutron-star systems.

Regular talk n.2

• Federico Carta (Istituto Nazionale di Fisica Nucleare)

Parametric, Crossing Symmetric Dispersion Relations for Quantum Field Theories

• Faizan Baht

We derive a new one-parameter family of manifestly crossing-symmetric dispersion relations for 2→2 scattering amplitudes in quantum field theories. We demonstrate that this parametric crossing-symmetric dispersion relation (PCSDR) both enlarges the convergence domain and improves the convergence rate relative to conventional fixed-t dispersion relations in many cases. For tree-level string-theory amplitudes, using the PCSDR, we obtain new series representations that exhibit poles in all the channels and converge in the full kinematic domain. We then apply this framework to bootstrap weakly coupled gravitational effective field theories and derive nontrivial bounds on their low-energy Wilson coefficients. Based on arXiv: 2506.03862 [hep-th].

Defect RG flows in ABJM theory from weak to strong coupling

• Diego Trancanelli (Istituto Nazionale di Fisica Nucleare)

Chern-Simons-matter theories in 3 dimensions are known to display a plethora of Wilson loops that can be used to define 1-dimensional defect conformal field theories (dCFTs) living on their contours. In this talk we propose to discuss a few examples from an intricate web of RG flows connecting the dCFTs defined on the BPS and non-BPS Wilson loops of ABJM theory. We compute the anomalous dimensions of the deforming operators, establish g-theorems along the flows, and also discuss the role played by cohomological anomalies and framing. We do this both at weak coupling in perturbation theory and at strong coupling, using the holographic duals of these operators. Based on: 2211.16501, 2305.01647, 2312.13283, 2410.10970, 2508.21068 and 2604.11896 with M. S. Bianchi, L. Castiglioni, S. Penati and M. Tenser.

Regular talk n.5

• Natalia Pinzani Fokeeva (Istituto Nazionale di Fisica Nucleare)

Generalised anomalies, QCD, and holography

• Mohammad Reza Ahkond (INFN Roma Tor Vergata)

During the last decade, the notion of an ’t Hooft anomaly has been generalised to the case of discrete symmetries. An interesting instance, discussed by Tanizaki, is the mixed anomaly between the discrete axial symmetry and the flavour and baryonic symmetries in massless QCD. In this talk, I will provide a derivation of this anomaly from a top-down holographic dual of QCD. I will show that the topological couplings in the bulk supergravity dual of the D4-D8 system encode Tanizaki’s anomaly. A technical challenge for this computation is the difficulty in maintaining gauge invariance of supergravity theories in the presence of D-branes. To overcome this issue, a compact formulation of the flux sector of (massive) type IIA supergravity in the presence of D8 branes is presented.

Review talk n.2

• Dionysios Anninos (King's College)

String theory in the infrared

• Ivano Basile (Max Planck Institute for Physics)

In the face of theoretical and experimental difficulties in directly probing string theory in its natural, high-energy regime, one hopes that its low-energy regime feature general properties arising from UV/IR mixing. Concretely, I will discuss how the infrared data - potentials, gauge couplings, Wilson coefficients - of gravitational effective theories arising from worldsheet string theory (specifically closed-string sectors at one-loop level) is constrained by conformal and modular invariance. I will comment on how the resulting scaling relations connecting these quantities reflects expectations from holographic and swampland considerations.

Bubbling saddles of the gravitational index

• Alejandro Ruiperez (University of Padova)

I will discuss a large class of supersymmetric solutions of Euclidean five-dimensional supergravity recently studied in 2507.12650 [hep-th]. These solutions admit an interpretation as saddle points of the gravitational path integral that computes a supersymmetric index. They possess a $\mathrm{U}(1)^3$ isometry and are characterized by a rod structure specifying the fixed loci of the $\mathrm{U}(1)$ isometries. These fixed loci can correspond either to horizons or to three-dimensional bubbles, and may have $S^3, S^1 \times S^2$, or lens-space topology. I will then focus on configurations containing a single horizon together with a bubble outside it, and show that these geometries correspond to saddles carrying the entropy of supersymmetric black rings and black lenses. Finally, time permitting, I will discuss a decoupling limit leading to asymptotically $\mathrm{AdS}_3$ solutions, and argue that a subclass of our geometries provides saddle points of the $\mathrm{AdS}​_3$ gravitational path integral computing the elliptic genus of the dual $\mathrm{CFT}_2$.

Universality of brane scattering from integrated correlators

• Francesco Galvagno (TO)

In this talk we will review some new achievements about the computation of integrated correlators in 4d SCFTs, which possess a dual holographic interpretation in terms of string scattering amplitudes in presence of D-branes. In particular, we will concentrate on two setups: (i) a class of correlators in $\mathcal{N}=4$ SYM with heavy operators dual to semiclassical D3-brane giant graviton solutions; (ii) integrated correlators in special $\mathcal{N}=2$ SCFTs with fundamental and antisymmetric matter content, dual to open/closed string amplitudes in presence of D7-branes. We make use of supersymmetric localization techniques to evaluate the integrated correlators in terms of a matrix model, generating exact results in the gauge coupling. The results from QFT side in the ’t Hooft limit show some remarkable universality properties for the string/brane scattering processes.

The Sausage Reheated

• Tommaso Pedroni (SISSA, Trieste)

The sausage model is a two-dimensional integrable deformation of the O(3) sigma model introduced by Fateev, Onofri and Zamolodchikov. In this talk I will explain how we can gain analytic access to the finite-size energy spectrum in the one-loop minisuperspace approximation using recently developed methods for Lamé and Heun equations, based on their relations to four-dimensional supersymmetric gauge theories and two-dimensional conformal field theories. In particular, this leads to explicit expressions for the energy levels near the two ends of the renormalization-group flow, and to quantitative control of the spectrum in the intermediate regime. Based on work in progress with G. Bonelli, S. Lacroix and A. Tanzini.

Heavy maximal-trace operators and their holographic duals

• Rudolf Treilis (University of Parma)

In this talk I will discuss a synthesis of ideas involving localization, modularity and resurgence that allows to one to make precision tests of holography. Localization allows us to compute the exact value of certain integrated 4-point functions of half-BPS operators; the form of these correlators is highly constrained by S-duality and they are modular functions. Then applying ideas from resurgence and solving the model in the large-N limit we find that both the perturbative and non-perturbative terms can be identified within a non-trivial deformation of $\mathrm{AdS}_5 \times S^5$, the so called AdS bubble - argued to be dual to a certain coherent state built from the 20' superconformal primary!

Regular talk n.12

• Chrysoula Markou (SNS, Pisa)

Regular talk n.13

• Nicolò Petri (INFN, Milano)

Celestial Mellin Amplitudes

• Paolo Pergola (Istituto Nazionale di Fisica Nucleare)

Celestial holography aims to recast flat-space physics in terms of conformal data on the celestial sphere. This invites the use of CFT techniques to analyse observables in flat holography. In this talk I will introduce a Mellin-amplitude representation for celestial correlators, inspired by the Mellin amplitudes for holographic correlators in AdS/CFT. Celestial Mellin amplitudes streamline both computation and interpretation of celestial correlators, and exhibit an AdS-like analytic structure: contact interactions give polynomial Mellin amplitudes, while particle exchange appears through a characteristic pattern of poles. After illustrating the method in scalar theories, we extend it to the exchange of spinning fields. For massless external scalars we obtain closed-form celestial Mellin amplitudes for spin-1 and spin-2 exchange (massless and massive) and extract direct-channel OPE data, identifying the contributions of the spin-1 current and the spin-2 stress tensor, together with the boundary gauge boson and graviton. Based on arXiv:2412.11992 and arXiv:2511.09501.

More on TTbar-like deformations in higher dimensions

• Nicolò Brizio

The TTbar deformation is a remarkable example of a solvable irrelevant deformation in two-dimensional quantum field theory. Its extension to higher dimensions is obstructed by the loss of factorisation and the onset of non-locality. In this talk, I discuss a class of TTbar-like deformations in $d>2$ formulated directly in terms of the stress-energy tensor. I show how these flows naturally lead to non-linear theories, including Dirac–Nambu–Goto and Born–Infeld–type actions, providing a unified perspective on their structure across dimensions. These results suggest that stress-tensor deformations offer a general framework to generate and organise non-linear field theories beyond two dimensions, with potential implications for integrability and locality.

Double and Multiple Copy at the Lagrangian Level

• Valerio Descontus (Istituto Nazionale di Fisica Nucleare)

The Double Copy relations allow one to compute (super-)gravitational scattering amplitudes from (super-)Yang-Mills ones. We explore this paradigm off-shell by attempting the construction of $\mathcal{N}=1$ and $\mathcal{N}=2$ Supergravity Lagrangians using suitably chosen pairs of (super-)Yang-Mills theories as building blocks. Our double-copy fields and gauge symmetries are defined as convolution products of single-copy Yang-Mills fields and parameters. When extended to higher spins, the model allows for an interpretation of the latter in terms of either double or multiple copies.

Regular talk n.17

• Alessandro Borys (University of Bologna)

Review talk "Semi-Classical Limits of Conformal Field Theories and Beyond"

• Zohar Komargodski (Simons Centre for Theoretical Physics)

Regular talk n.18

• Alessandro Duci

Regular talk n.19

• Pierluigi Niro (SISSA, Trieste)

Regular talk n.20

• Palash Singh (Università degli Studi di Milano-Bicocca)

Regular talk n.21

• Guo Hengyuan