Séminaire de Carlota Andres-Casas, 21/11/2024, 11h, au CPHT, Salle JEAN LASCOUX

Probing the Quark-Gluon Plasma with Energy Correlators

Recent advances in conformal field theory have led to the reformulation of collider jet substructure as the study of correlation functions of the energy flux, known as energy correlators, and their associated light-ray operator product expansion (OPE). Multi-point energy correlators have been measured in proton-proton collisions at the Large Hadron Collider (LHC), offering experimental validation of the light-ray OPE. In this talk, I will highlight the advantages of using energy correlators to probe the quark-gluon plasma produced in heavy-ion collisions, for which the first energy correlator measurement has recently been unveiled. Building on the unique properties of energy correlators, I will introduce a novel observable that stands as the first heavy-ion jet substructure observable where energy loss (or selection bias) is not the leading effect.

Séminaire en physique mathématique, le lundi 18 novembre 2024, à 14h, au CPHT, salle Louis Michel

Jürg Fröhlich (ETH Zürich)

"The stochastic evolution of isolated systems in quantum mechanics"

Abstract: In this talk I describe a Law of Dynamics for non-relativistic Quantum Mechanics (QM). The time evolution of physical systems consisting of charged matter interacting with the quantized electromagnetic field, e.g., electrons in the shell of an atom coupled to the radiation field, is non-linear, dissipative and stochastic, featuring isolated random events sometimes called “quantum jumps”. We discuss the equations describing it ! They involve a new type of stochastic process, dubbed “quantum Poisson jump process." An application to the phenomenon of fluorescence will be sketch

Le séminaire des jeunes chercheurs du CPHT aura lieu le jeudi 14 novembre 2024 à 14h00 à la Salle de conférence Jean Lascoux avec deux présentations :

Owen Colire : Elements of single-particle theory for electrons in solids

Victor Dubois : Introduction to plasma physics and magnetic confinement

Le séminaire sera suivi d'un goûter.

We are happy to launch a new thematic trimester on New trends in QFT, modularity and resurgence.
We will start with an in-person kick-off event on November 6, from 13:30 to 17:30, at Institut Henri Poincaré, Paris.

We are very excited about the contributions from our three speakers for this event:

Antoine Tilloy (LPENS, Mines Paris, Inria) - A variational approach to QFT in low dimensions?

Campbell Wheeler (IHES) - Matrix cocycles and Borel resummation

Claudia Rella (IHES) - The arithmetic of resurgent topological strings

To attend our kick-off event in person, there is a free but mandatory registration: https://seedseminar.apps.math.cnrs.fr/registration

We will also share a Zoom link via this mailing list for those of you who cannot make it in person.
After the kick-off event of November 6, the trimester will continue with our traditional online talks every two weeks, which will be delivered as hybrid events at the IHES (more info soon). Details will be announced via this list.
For further information: https://seedseminar.apps.math.cnrs.fr

Kind regards,
Matteo D’Achille, Aymane El Fardi, Veronica Fantini, Emmanuel Kammerer, Edoardo Lauria, Sophie Mutzel, Junchen Rong

Mailing list of the Seed Seminar of Mathematics and Physics More info at: https://seedseminar.apps.math.cnrs.fr/
 

Une nouvelle approche pour évaluer l’avancée des techniques de simulation en physique quantique

Dans un article publié dans la revue Science, une collaboration internationale, à laquelle participent des chercheurs du Centre de physique théorique, propose un outil pour estimer la difficulté de nombreux problèmes en physique quantique qui restent à résoudre ainsi que l’efficacité des méthodes développées pour s’y attaquer, y compris les algorithmes quantiques.

Lien vers la publication scientifique: Variational benchmarks for quantum many-body problems, Science, 386, 6719, 2024. DOI: 10.1126/science.adg9774

Lire le communiqué de l'Ecole polytechnique

Adrien Loty soutiendra publiquement ses travaux de thèse le 21 octobre 2024 à 15h30 à l'Ecole polytechnique, amphi Carnot

Titre : Constraints on the action of effective theories in quantum gravity

Directeur de thèse : Guillaume Bossard

La soutenance sera suivi du pot de thèse.

Tuesday 08/10 at 14:30

at CPHT, Conference room Louis Michel

B. J. Kim (POSTECH, Republic of Korea)

Origin of chirality in the charge density wave semimetal 1T-TiSe2

Abstract: Chirality is a ubiquitous phenomenon in which a symmetry between left- and right-handed objects is broken, examples in nature ranging from subatomic particles and molecules to living organisms. However, mechanisms that lead to chirality in condensed matter systems remain poorly understood. In this talk, I will discuss on a novel mechanism of chiral charge density wave formation in the transition-metal dichalcogenide 1T-TiSe2. Based on a rigorous symmetry analysis, we show that charge density modulations and ionic displacements, which transform as a continuous scalar field and a vector field on a discrete lattice, respectively, follow different irreducible representations of the space group, despite the fact that they propagate with the same wave-vectors and are strongly coupled to each other. This charge-lattice symmetry frustration is resolved by further breaking of all symmetries not common to both sectors through induced lattice distortions, thus leading to chirality. Our theory is verified using Raman spectroscopy and inelastic x-ray scattering, which reveal that all but translation symmetries are broken at a level not resolved by state-of-the-art diffraction techniques.

Le séminaire des jeunes chercheurs du CPHT aura lieu le jeudi 3 octobre 2024 à 15h00 à la Salle de conférence Louis Michel avec deux présentations :

Magali Korolev : Charge fractionalization in quantum wires

Thomas Pochart : An introduction to axiomatic quantum field theory

Le séminaire sera suivi d'un goûter.

Arseny Mironov, qui a réussi le concours CRCN cette année, rejoindra le CPHT le 1er décembre 2024. Il sera rattaché au groupe de théorie des plasmas. Arseny étudie des effets quantiques dans des champs électromagnétiques extrêmes, notamment en lien avec des expériences futures visant à explorer de nouveaux régimes d'interaction rayonnement-matière dans des installations laser multi-petawatt (y compris Apollon) et des collisionneurs de leptons.

Carlota Andrés est lauréate de l'ERC starting grant 2024 avec son projet "QGPthroughEEC (Quark Gluon Plasma through Energy-Energy Correlators) : Mieux comprendre le plasma de quarks et de gluons". Ce projet est porté par l'Ecole polytechnique. Plus d'informations : ici

Ayant effectué un post-doctorat au CPHT entre 2021 et 2023, puis à Lisbonne, elle a poursuivi ses recherches à Boston. Elle revient au CPHT en juillet 2025 pour y occuper un poste en tenure track