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

Post-doctorante au CPHT de 2021 à 2023 dans l'équipe Physique des particules, elle a ensuite était post-doctorante à Lisbonne. Elle est actuellement à Boston. Elle rejoindra le CPHT en juillet 2025 pour un poste permanent.

Une nouvelle approche théorique du problème quantique à N corps a été développée, qui donne pour la première fois accès à une estimation rigoureuse des erreurs commises par les solutions approximatives calculées par des simulations numériques utilisant des méthodes traditionnelles.

Ces travaux ont été conduits par une collaboration entre l'ICFO (Espagne), le Laboratoire Kastler Brossel (LKB, CNRS / Collège de France / ENS-PSL / Sorbonne Université), l'Institut Néel (CNRS / Université Grenoble Alpes), l'Academy of Mathematics and Systems Science (Chine), le Perimeter Institute for Theoretical Physics (Canada), le Centre de Physique Théorique (CPHT, CNRS / Ecole Polytechnique), le Laboratoire d'Analyse et d'Architecture des Systèmes (LAAS) et le Département d'Ingénierie Electrique (ESAT / KU Leuven). Ils sont publiés dans Physical Review X.

Plus d'information : CNRS PHYSIQUE / Actualités

CARROLL PHYSICS, ASYMPTOTIC SYMMETRIES AND CONFORMAL FIELD THEORIES

ARISTOTLE UNIVERSITY OF THESSALONIKI
Laboratory of Theoretical Physics
23 September 2024

Aspects of Cosmology: Mathematics and Physics
Ecole Polytechnique – Becquerel Amphitheatre
September 25-27 2024

The aim of this conference is to bring together mathematicians and physicists working on fields related to cosmology, which has been the subject of tremendous investigations in the past few years.

Properties of the gravitational wave background have been thoroughly explored in recent years, including their generation, propagation and detection. Progress has also been made in a unified description of weak and strong gravitational lensing, as well as in numerical and analytical analysis of the large scale structure of the universe. New properties of inflationary and de Sitter spacetimes have been uncovered, both at the classical and quantum level. In contrast, for alternative theories of gravitation with good ultraviolet behaviour, such as string theory, de Sitter-type solutions cannot emerge, and we now have a more rigorous understanding why this happens. Significant results have been reached in the design of valid quintessence scenarios using the dynamical systems approach to differential equations.

On the mathematical side, successes have been achieved toward understanding the nature of the big bang singularity and the behaviour of general solutions in its vicinity. The stability of FLRW solutions has also been the subject of various studies.

The conference will take place in Ecole Polytechnique (Amphi Becquerel), Palaiseau, from September 25th to September 27th.

Registration is free but mandatory : https://cosmology.sciencesconf.org
Some fundings may be available for graduate students. For this, don't hesitate to write at cosmology@sciencesconf.org

Schedule

Poster