Théorie des cordes

 

Annuaire du groupe Recherche Evénements Offres de poste

 

 

Coordinateur : Marios Petropoulos

  • Membres permanents

Guillaume Bossard
Emilian Dudas
Blaise Goutéraux
Hervé Partouche
Andrea Puhm

  • Doctorants

Gabriele Casagrande
Silvia Georgescu
Adrien Loty
Yorgo Pano
David Rivera Betancour
Filippo Sottovia
Balthazar de Vaulchier
Matthieu Vilatte

  • Post-doctorants

Daniel Brattan
Sangmin Choi
Blagoje Oblak
Marija Tomašević
Emilio Trevisani
Vaios Ziogas

  • Chercheur associé

Ashish Shukla (arrivée Février 2022)

 

Activités de recherche du groupe

L’activité du groupe Théorie des Cordes au CPHT couvre un large éventail de sujets allant des aspects
mathématiques de la théorie des cordes à des applications dans les domaines de la gravitation, de la
physique des particules, de la cosmologie et de la physique de la matière condensée. Beaucoup de ces
sujets ont connu des avancées majeures grâce à la dualité holographique jauge-gravité qui offre une
formulation non perturbative de la théorie des cordes.

 

Actualités

AdS/CMT seminar le mardi 14 décembre 2021 à 11h00

au CPHT, Salle de conférence Louis Michel

Richard Davison (Heriot-Watt University, Scotland)

"Chaos and pole-skipping in rotating black holes"

Abstract: Out-of-time-ordered correlators of local operators (OTOCs) provide a way of characterising scrambling and chaos in quantum field theory states. For states with a classical, static black hole description, these correlators decay in a universal manner that is quantitatively related to a 'pole-skipping' property of the Green's function of the energy density operator. This is consistent with a hydrodynamic effective theory for chaos in these states. In this talk I will discuss how these results generalise to the rotating, thermal state dual to the Kerr-AdS black hole. In the limit of slow rotation I will present an explicit form of the OTOC and show how its form can be used to obtain exact constraints on the dispersion relations of the collective modes that carry energy.

AdS/CMT seminar le vendredi 10 décembre 2021 à 11h00

au CPHT, Salle de conférence Louis Michel

Sebastian Grieninger (IFT Madrid)

"(Pseudo)-Spontaneous U(1) Symmetry Breaking in Hydrodynamics and Holography"

Abstract: We investigate the low-energy dynamics of systems with (pseudo)-spontaneously broken U(1) symmetry. First, we consider the purely spontaneous case which corresponds to a superfluid where we compute the support of the hydrodynamic modes on the different field theory operators across the phase diagram. In the pseudo-spontaneous case, we construct a hydrodynamic framework and consider two generalizations of the standard holographic superfluid model to incorporate explicit breaking. In all cases, we find agreement between hydrodynamics and holography. Furthermore, we verify that phase relaxation arises only due to the breaking of the inherent Goldstone shift symmetry. The interplay of a weak explicit breaking of the U(1) and phase relaxation renders the DC electric conductivity finite but does not result in a Drude-like peak. In this scenario we show the validity of a universal relation between the phase relaxation rate, the mass of the pseudo-Goldstone and the Goldstone diffusivity.

Séminaire des cordes le jeudi 9 décembre 2021 à 16h00

sur Zoom

Anomalies and Emergent Symmetries on the Lattice and in the Continuum
Shu-Heng Shao (Stony Brook University)

We consider various standard and exotic lattice models, and deform them using an approach generalizing the Villain formulation. The new lattice models exhibit many properties that were thought to be exclusive to the continuum field theories. These include exact winding/magnetic symmetries, anomalies, and new dualities. We apply this approach to the standard XY model, ZN clock model, gauge theories, and exotic models related to fractons.

Séminaire des cordes le lundi 22 novembre 2021 à 11h00

au CPHT, Salle de conférence Louis Michel

Chern-Simons supergravity and black holes with unbroken supersymmetries
Olivera Mišković (PUCV, Valparaiso, Chile)

We study particular supersymmetric extension of Einstein-Gauss-Bonnet AdS gravity in five dimensions. The theory admits black hole solutions with non-trivial topological properties, which are also BPS states that leave some of the supersymmetries unbroken. We analyse physical properties of these solutions, such as their conserved charges and topological numbers. We find many similarities of these solutions with standard supergravity black holes, and also with three-dimensional BTZ geometries.

 

Conformal renormalization in AdS gravity
Rodrigo Olea (UNAB, Santiago, Chile)

We present evidence that the renormalization of Einstein-AdS gravity can be derived from conformal structures in the bulk. In point of fact, by applying a holographic mechanism which reduces Conformal Gravity to its Einstein sector in 4 and 6 dimensions, the Einstein-AdS action is naturally endowed with the correct counterterms.

Séminaire des cordes le vendredi 8 octobre 2021 à 15h00

au CPHT, Salle de conférence Louis Michel

Anastasios Petkou

"On scale, conformal and Weyl invariance in QFT"

Abstract: Scale, conformal and Weyl invariance play a central role in Quantum Field Theories, and they are omnipresent in AdS/CFT correspondence. Through various examples I will review various issues and possible misconceptions regarding the interrelationships between these three important notions and connect them to some recent investigations.

 

Andrea Puhm sur France Culture le 16 février 2021

Andrea Puhm, chargée de recherche au Centre de Physique Théorique a été invitée à parler du paradoxe de l'information des trous noirs dans l'émission " La méthode scientifique" sur France ulture le 16 février 2021.

En savoir plus ici.

 

Postdoctoral position(s) ERC "Hydrodynamics, Holography and strongly-coupled Quantum Matter" at  the Center for Theoretical Physics, Ecole Polytechnique

Contact : Blaise Goutéraux

Dates
Date limite de candidature : 30 novembre 2020
Résultat des candidatures : décembre 2020 - janvier 2021
Date de début du contract : 1er septembre 2021 (negociable)

En savoir plus

 

Postdoctoral Position(s) ERC Starting Grant 'Information Encoding in Quantum Gravity and the Black Hole Information Paradox'

Contact : Andrea Puhm

Dates
Date limite de candidature : 30 novembre 2020
Résultat des candidatures : décembre 2020 - janvier 2021
Date de début du contract : 1er octobre2021 (negociable)

En savoir plus

Gravity and Strings Conference
26 september 2019, Ecole Polytechnique, CPHT, Salle Louis Michel, 10AM - 6PM

Organized by Luca Ciambelli

Speakers :

Carlo Angelantonj
Stéphane Detournay
Rodrigo Olea
Anastasios Petkou
Marios Petropoulos
Céline Zwikel

 

 

Andrea Puhm sur France Culture le 10 septembre 2019

Andrea Puhm, chargée de recherche au Centre de Physique Théorique a été invitée à parler de supergravité dans l'émission " La méthode scientifique" sur France ulture le 10 septembre 2019.

En savoir plus ici.

 

Andrea Puhm, lauréate de l’ERC Starting Grant 2019

Chargée de recherche du CNRS au Centre de physique théorique de l’École polytechnique, Andrea Puhm a été distinguée par une bourse ERC Starting Grant qui va lui permettre de lancer un groupe de recherche sur la thématique «Codage d'information en gravité quantique et le paradoxe d'information des trous noirs».

En savoir plus ici

 

Séminaire des cordes le lundi 22 novembre 2021 à 11h00

au CPHT, Salle de conférence Louis Michel

Chern-Simons supergravity and black holes with unbroken supersymmetries
Olivera Mišković (PUCV, Valparaiso, Chile)

We study particular supersymmetric extension of Einstein-Gauss-Bonnet AdS gravity in five dimensions. The theory admits black hole solutions with non-trivial topological properties, which are also BPS states that leave some of the supersymmetries unbroken. We analyse physical properties of these solutions, such as their conserved charges and topological numbers. We find many similarities of these solutions with standard supergravity black holes, and also with three-dimensional BTZ geometries.

 

Conformal renormalization in AdS gravity
Rodrigo Olea (UNAB, Santiago, Chile)

We present evidence that the renormalization of Einstein-AdS gravity can be derived from conformal structures in the bulk. In point of fact, by applying a holographic mechanism which reduces Conformal Gravity to its Einstein sector in 4 and 6 dimensions, the Einstein-AdS action is naturally endowed with the correct counterterms.

 

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