Publications de Riccardo Rattazzi

Superadditivity at large charge

The weak gravity conjecture has been invoked to conjecture that the dimensions of charged operators in a CFT should obey a superadditivity relation (sometimes referred to as convexity). In this paper, we study superadditivity of the operator spectrum in th ...

Springer Science and Business Media LLC2025

Exploring the flavor symmetry landscape

Riccardo Rattazzi

We explore flavor dynamics in the broad scenario of a strongly interacting light Higgs (SILH). Our study focuses on the mechanism of partial fermion compositeness, but is otherwise as systematic as possible. Concretely, we classify the options for the unde ...

Stichting SciPost2025

The quantum perfect fluid in 2D

Riccardo Rattazzi

We consider the field theory that defines a perfect incompressible 2D fluid. One distinctive property of this system is that the quadratic action for fluctuations around the ground state features neither mass nor gradient term. Quantum mechanically this po ...

2024

Tetraquarks at large M and large N

Riccardo Rattazzi, Majid Ekhterachian, Filippo Nardi

We study tetraquarks in large N QCD with heavy quarks, in the domain where non-relativistic quantum mechanics offers an adequate approximation. Within the regime of validity of the Born-Oppenheimer approximation, we systematically study and explicitly cons ...

Springer Nature2024

Towards a muon collider (vol 83, 864, 2023)

Niko Neufeld, Riccardo Rattazzi, Xavier Buffat, Andrea Wulzer, Roberto Franceschini, Varun Sharma, Alexej Grudiev, Riccardo Torre, Marco Valente, Ennio Salvioni, Jing Shu, Marco Calviani, Luca Bottura, Tao Han, Xin Sun, Siyu Chen, Alfredo Glioti, Xiaoran Zhao, Lorenzo Ricci, Jian Tang, Alessandro Valenti, Brian Quinn Henning, Filippo Nardi, Laura Buonincontri, Luca Giambastiani

Springer2024

Flux correlators and semiclassics

Riccardo Rattazzi, Alexander Monin, Eren Clément Firat, Matthew Thomas Walters

We consider correlators for the flux of energy and charge in the background of operators with large global U(1) charge in conformal field theory (CFT). It has recently been shown that the corresponding Euclidean correlators generically admit a semiclassica ...

Springer Nature2024

Identifying Large Charge operators

Riccardo Rattazzi, Alexander Monin, Gil Badel

The Large Charge sector of Conformal Field Theory (CFT) can generically be described through a semiclassical expansion around a superfluid background. In this work, focussing on U(1) invariant Wilson-Fisher fixed points, we study the spectrum of spinning l ...

Springer Nature2023

Softening the UV without new particles

Riccardo Rattazzi

We explore an odd class of quantum field theories where a hierarchy problem is resolved with new dynamics as opposed to new particles. The essential element of our construction is a U(1) pseudo-NambuGoldstone boson with symmetry breaking interactions all c ...

American Physical Society2023

Towards a muon collider

Niko Neufeld, Riccardo Rattazzi, Xavier Buffat, Andrea Wulzer, Roberto Franceschini, Varun Sharma, Alexej Grudiev, Riccardo Torre, Marco Valente, Ennio Salvioni, Jing Shu, Marco Calviani, Luca Bottura, Tao Han, Xin Sun, Siyu Chen, Alfredo Glioti, Xiaoran Zhao, Lorenzo Ricci, Jian Tang, Alessandro Valenti, Brian Quinn Henning, Filippo Nardi, Laura Buonincontri, Luca Giambastiani

A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by ...

Springer2023

The role of the pion in the lineshape of the X(3872)

Riccardo Rattazzi, Alfredo Glioti, Angelo Esposito

We determine the contribution of long-range pion interactions to the X(3872) dynamics, assuming it is a loosely bound D-0(D) over bar*(0) molecule. Our result is based on the distorted wave Born approximation in non-relativistic quantum mechanics. Despite ...

Elsevier2023

Learning from radiation at a very high energy lepton collider

Riccardo Rattazzi, Andrea Wulzer, Siyu Chen, Alfredo Glioti, Lorenzo Ricci

We study the potential of lepton collisions with about 10 TeV center of mass energy to probe Electroweak, Higgs and Top short-distance physics at the 100 TeV scale, pointing out the interplay with the long-distance (100 GeV) phenomenon of Electroweak radia ...

Springer Nature2022

Positive moments for scattering amplitudes

Francesco Riva, Riccardo Rattazzi, Marc Riembau Saperas, Brando Bellazzini

We find the complete set of conditions satisfied by the forward 2 -> 2 scattering amplitude in unitary and causal theories. These are based on an infinite set of energy dependent quantities (the arcs) which are dispersively expressed as moments of a positi ...

American Physical Society2021

Gapped Goldstones at the cut-off scale: a non-relativistic EFT

Riccardo Rattazzi, Alexander Monin, Gabriel Francisco Cuomo, Angelo Esposito

At finite density, the spontaneous breakdown of an internal non-Abelian symmetry dictates, along with gapless modes, modes whose gap is fixed by the algebra and proportional to the chemical potential: the gapped Goldstones. Generically the gap of these sta ...

Springer Nature2021

Feynman diagrams and the large charge expansion in 3-epsilon dimensions

Riccardo Rattazzi, Alexander Monin, Gil Badel, Gabriel Francisco Cuomo

In arXiv:1909.01269 it was shown that the scaling dimension of the lightest charge n operator in the U (1) model at the Wilson-Fisher fixed point in D = 4 - epsilon can be computed semiclassically for arbitrary values of lambda n, where lambda is the pertu ...

2020

Higgs Boson studies at future particle colliders

Riccardo Rattazzi

This document aims to provide an assessment of the potential of future colliding beam facilities to perform Higgs boson studies. The analysis builds on the submissions made by the proponents of future colliders to the European Strategy Update process, and ...

Springer Nature2020

The epsilon expansion meets semiclassics

Riccardo Rattazzi, Alexander Monin, Gil Badel, Gabriel Francisco Cuomo

We study the scaling dimension Delta(phi n) of the operator phi(n) where phi is the fundamental complex field of the U(1) model at the Wilson-Fisher fixed point in d = 4 - epsilon. Even for a perturbatively small fixed point coupling lambda*, standard pert ...

Springer Nature2019

Electroweak baryogenesis above the electroweak scale

Riccardo Rattazzi, Luca Vecchi, Alfredo Glioti

Conventional scenarios of electroweak (EW) baryogenesis are strongly constrained by experimental searches for CP violation beyond the SM. We propose an alternative scenario where the EW phase transition and baryogenesis occur at temperatures of the order o ...

Springer Nature2019

Rotating superfluids and spinning charged operators in conformal field theory

Riccardo Rattazzi, Alexander Monin, David Pirtskhalava, Anton Reyes De La Fuente, Gabriel Francisco Cuomo

American Physical Society2018

Semiclassics, Goldstone bosons and CFT data

Riccardo Rattazzi, Alexander Monin, Fiona Katharina Seibold, David Pirtskhalava

Hellerman et al. (arXiv:1505.01537) have shown that in a generic CFT the spectrum of operators carrying a large U(1) charge can be analyzed semiclassically in an expansion in inverse powers of the charge. The key is the operator state correspondence by whi ...

Springer Nature2017

What is the gamma gamma resonance at 750 GeV?

Francesco Riva, Riccardo Rattazzi, Michele Redi, Roberto Franceschini, Riccardo Torre

Run 2 LHC data show hints of a new resonance in the diphoton distribution at an invariant mass of 750 GeV. We analyse the data in terms of a new boson, extracting information on its properties and exploring theoretical interpretations. Scenarios covered in ...

Springer Nature2016