Séminaire / Seminar GReCO |
| « A Match Made in Heaven: Linking Observables in Inflationary Cosmology » |
|
Xi Tong |
| The non-Gaussian statistics of primordial perturbations is a pristine tracer of new physics in the early universe. Given a specific inflationary Lagrangian, different late-time correlators are traditionally computed independently using diagrammatics. However, such computations work diagram-by-diagram and are often obscured by technical mathematical challenges. In this talk, I will show that different correlator observables are, in fact, not independent. Rather, there exist subterranean connections among correlators that bypass the technical complexities. Starting from generic assumptions, I will establish a reality theorem which then translates to an infinite family of algebraic relations, thereby linking higher-point correlators to lower-point ones. As a concrete application, I will show that the parity-odd curvature trispectrum is a “double-copy” of the curvature-graviton mixed bispectrum whenever a gravitational Chern-Simons term is involved. Such relations are the first cosmological cutting rules that can be observationally tested and serve as a smoking gun towards physics in the primordial universe. |
|
lundi 24 mars 2025 - 11:00 Salle des séminaires Évry Schatzman Institut d'Astrophysique de Paris |
| Pages web du séminaire / Seminar's webpage |