|
|
|
Le serveur de séminaires SEMPARIS accueille toutes les annonces de séminaires de la région parisienne, dans tous les domaines de la physique et des mathématiques. Il vous permet aussi de recevoir par courrier électronique la sélection de votre choix. Enfin, il permet l'archivage des présentations au format PDF ou Powerpoint. [ Plus d'informations ]
| Séminaires à venir dans la série RENC-THEO | ||
| [ vue agenda ] | ||
| Jeudi 16 Janvier 2025, 10:00 à IHP, Grisvard (314) | RENC-THEO (Rencontres Théoriciennes) | hep-th |
|
|
|
|
| Abstract: | The asymptotic structure of spacetime with a vanishing cosmological constant is central to discussing gravitational radiation and gravitational scattering. In asymptotically flat spacetimes, the peeling property prescribes a decay rate for the Weyl tensor as one approaches the null boundary. However, there are compelling motivations for relaxing this peeling condition, leading to a polyhomogeneous rather than polynomial expansion in Bondi gauge. In this talk, I will review these motivations and explore the implications of introducing logarithmic terms into the asymptotic expansion. I will discuss how these modifications affect the symmetry structure of such spacetimes and the consequences on soft theorems. Furthermore, I will present new logarithmic evolution equations and flux-balance laws, which point to the existence of an infinite hierarchy of subleading logarithmic soft graviton theorems. (basé sur 2407.07978 ) | |
| Jeudi 16 Janvier 2025, 11:45 à IHP, Grisvard (314) | RENC-THEO (Rencontres Théoriciennes) | hep-th |
|
|
|
|
| Abstract: | Holographic CFTs possess a certain point in moduli space where there is a weakly coupled gravity dual. Computing the first non-trivial term in a four-point function using this description used to involve tedious work but much of this has now been superseded by bootstrap methods. In the case of AdS_5 x S^5 supergravity, there are now compact expressions for infinitely many tree-level four-point functions and these have served as a stepping stone towards correlators with loops, stringy corrections and more external legs. AdS_3 x S^3 is another supergravity background with a close connection to known holographic CFTs but it has not yet been put on the same footing. In this talk, I will explain why the obstacles are less daunting than they used to be and how they can be overcome with a formalism based on multiple Mellin amplitudes. | |
| Jeudi 13 Fevrier 2025, 10:00 à IHP, Pierre Grisvard | RENC-THEO (Rencontres Théoriciennes) | hep-th |
|
|
|
|
Vous êtes invité à vous abonner aux listes de distribution SEMPARIS afin de recevoir les annonces par courriel.
|
|
[ English version ] |