Séminaire / Seminar GReCO | 
| « Beyond perturbation theory in inflation » | 
| 
	 Vicharit Yingcharoenrat  | 					
| In this talk I will first discuss a motivation why one needs to go beyond perturbation theory (PT) in inflation as going to the tail of the distribution of the primordial fluctuations. Then I will propose that the way to go beyond PT is equivalent to performing a calculation in the semi-classical limit. As an analogy, I will show a simple calculation of the ground-state wavefunction in the semi-classical limit for an anharmonic oscillator. After that, I will move to a toy model of inflation which for simplicity involves only derivative couplings. As a result, the wavefunction of the Universe in this semi-classical limit exhibits a non-perturbative behaviour in the large field limit. | 
| 
	lundi 19 avril 2021 - 11:00  Webinaire Institut d'Astrophysique de Paris  | 
| Pages web du séminaire / Seminar's webpage |