Publications associées à Identifying Large Charge operators

Publications associées (44)

Self-congruent point in critical matrix product states: An effective field theory for finite-entanglement scaling

We set up an effective field theory formulation for the renormalization flow of matrix product states (MPS) with finite bond dimension, focusing on systems exhibiting finite-entanglement scaling close to a conformally invariant critical fixed point. We sho ...

2025

Lepton flavour universality tests and lepton flavour violation searches at LHCb

Sara Celani

The Standard Model (SM) of particle physics represents our most fundamental knowledge of elementary particles and their interactions. One of the cardinal properties of the SM which has been thoroughly studied during the past years is the so-called Lepton F ...

Stichting SciPost2025

A dephasing sweet spot with enhanced dipolar coupling

Pasquale Scarlino

Two-level systems (TLSs) are the basic units of quantum computers but face a trade-off between operation speed and coherence due to shared coupling paths. Here, we investigate a TLS given by a singlet-triplet (ST+) transition. We identify a magnetic-field ...

2025

Three-point correlation functions in the $\mathfrak{sl}_{3}$ Toda theory II: The Fateev–Litvinov formula

Baptiste Yves Philippe Cerclé

Toda conformal field theories (CFTs) form a family of two-dimensional CFTs indexed by semisimple and complex Lie algebras. One of their remarkable features is that they are natural generalizations of Liouville CFT that enjoy an enhanced level of symmetry, ...

European Mathematical Society - EMS - Publishing House GmbH2025

Search for excited tau leptons in the ττγ final state in proton-proton collisions at = 13 TeV

Jan Steggemann, Konstantin Androsov, Anna Mascellani, Joanna Malgorzata Wanczyk, Paul Théodore Gabriel Pablo De Bryas Dexmiers d'Archiac

Results are presented for a test of the compositeness of the heaviest charged lepton, τ, using data collected by the CMS experiment in proton-proton collisions at a center-of-mass energy of 13 TeV at the CERN LHC. The data were collected in 2016–2018 and c ...

Springer2025

Field-controlled multicritical behavior and emergent universality in fully frustrated quantum magnets

Bruce Normand

Phase transitions in condensed matter are a source of exotic emergent properties. We study the fully frustrated bilayer Heisenberg antiferromagnet to demonstrate that an applied magnetic field creates a previously unknown emergent criticality. The quantum ...

Nature Portfolio2024

Search for Long-Lived Heavy Neutral Leptons with Muons at the CMS Experiment and Characterisation of Scintillating Fibre Trackers

Anna Mascellani

This PhD thesis presents a search for Heavy Neutral Leptons (HNLs) using data collected by the CMS experiment at the CERN Large Hadron Collider (LHC). HNLs are hypothetical new particles proposed in several theoretical extensions of the Standard Model (SM) ...

EPFL2025

Holography and localization of information in quantum gravity

Kyriakos Papadodimas, Alexandre Mathieu Frédéric Belin

Within the AdS/CFT correspondence, we identify a class of CFT operators which represent diff-invariant and approximately local observables in the gravitational dual. Provided that the bulk state breaks all asymptotic symmetries, we show that these operator ...

Springer Nature2024

Exact quantum conformal symmetry, its spontaneous breakdown, and gravitational Weyl anomaly

Mikhail Chapochnikov, Anna Tokareva

The classical Lagrangian of the Standard Model enjoys the symmetry of the full conformal group if the mass of the Higgs boson is put to zero. This is a hint that conformal symmetry may play a fundamental role in the ultimate theory describing nature. The o ...

American Physical Society2023

The Källén-Lehmann representation in de Sitter spacetime

João Miguel Augusto Penedones Fernandes, Kamran Salehi Vaziri, Manuel Loparco

We study two-point functions of symmetric traceless local operators in the bulk of de Sitter spacetime. We derive the Kallen-Lehmann spectral decomposition for any spin and show that unitarity implies its spectral densities are nonnegative. In addition, we ...

Springer Nature2023

Twist Accumulation in Conformal Field Theory: A Rigorous Approach to the Lightcone Bootstrap

Jiaxin Qiao

We prove that in any unitary CFT, a twist gap in the spectrum of operator product expansion (OPE) of identical scalar quasiprimary operators (i.e. phi x phi) implies the existence of a family of quasiprimary operators O t,l with spins l ->.infinity and twi ...

SPRINGER2023

Anomaly-free scale symmetry and gravity

Mikhail Chapochnikov, Anna Tokareva

In this Letter, we address the question of whether the conformal invariance can be considered as a global symmetry of a theory of fundamental interactions. To describe Nature, this theory must contain a mechanism of spontaneous breaking of the scale symmet ...

ELSEVIER2023

Nonperturbative aspects of scattering amplitudes

Miguel Alexandre Ribeiro Correia

In this thesis we study how physical principles imposed on the S-matrix, such as Lorentz invariance, unitarity, crossing symmetry and analyticity constrain quantum field theories at the nonperturbative level. We start with a pedagogical introduction to the ...

EPFL2023

Bootstrapping traceless symmetric O(N) scalars

Alessandro Vichi, Maria Refinetti, Marten Jan Reehorst

We use numerical bootstrap techniques to study correlation functions of traceless sym-metric tensors of O(N) with two indices ti j. We obtain upper bounds on operator dimen-sions for all the relevant representations and several values of N. We discover sev ...

SCIPOST FOUNDATION2023

Hilbert series, the Higgs mechanism, and HEFT

Brian Quinn Henning

We expand Hilbert series technologies in effective field theory for the inclusion of massive particles, enabling, among other things, the enumeration of operator bases for non-linearly realized gauge theories. We find that the Higgs mechanism is manifest a ...

Springer Nature2023

Critical properties of the quantum Ashkin-Teller chain with chiral perturbations

Frédéric Mila, Natalia Chepiga

We investigate the nature of the phase transitions in the quantum Ashkin-Teller chain in the presence of chiral perturbations. We locate the Lifshitz line separating a region of direct chiral transitions from the region where the transition is through an i ...

Amer Physical Soc2023

Many-body physics with strongly interacting fermions coupled to light

Victor Youri Helson

This thesis reports on the realization of the first experiments conducted with superfluid, strongly interacting Fermi gases of 6Li coupled to the light field of an optical cavity. In the scope of existing ultracold atomic platforms, this is the first time ...

EPFL2023

Characterization of two electronic subsystems in cuprates through optical conductivity

Ana Akrap, Edoardo Martino, Neven Barisic

Understanding the physical properties of unconventional superconductors as well as of other correlated materials presents a formidable challenge. Their unusual evolution with doping, frequency, and temperature has frequently led to non-Fermi-liquid (non-FL ...

2023

Momentum-resolved spin-conserving two-triplon bound state and continuum in a cuprate ladder

Henrik Moodysson Rønnow, Thorsten Schmitt, Yi Tseng

Studying multi-particle elementary excitations has provided unique access to understand collective many-body phenomena in correlated electronic materials, paving the way towards constructing microscopic models. In this work, we perform O K-edge resonant in ...

NATURE PORTFOLIO2023

Density-wave ordering in a unitary Fermi gas with photon-mediated interactions

Jean-Philippe Brantut, Victor Youri Helson, Kevin Etienne Robert Roux, Hideki Konishi, Timo Zwettler

A density wave (DW) is a fundamental type of long-range order in quantum matter tied to self-organization into a crystalline structure. The interplay of DW order with superfluidity can lead to complex scenarios that pose a great challenge to theoretical an ...

NATURE PORTFOLIO2023