[NTU-NCTS String Seminar] A geometric approach to the perturbative unitarity in cosmology

  • Event Date: 2023-05-31
  • High energy theory
  • Speaker: Dr. Soner Albayrak (Univ. of Amsterdam)  /  Host: Profs. Yu-tin Huang & Pei-Ming Ho (NTU)
    Place: Rm. 815, Dept. of Physics, NTU

Title: [NTU-NCTS String Seminar] A geometric approach to the perturbative unitarity in cosmology
Speaker: Dr. Kamran Salehi (Univ. of Amsterdam)
Time: May. 31, 2023 (Thur.) 14:30-15:30
Venue: Rm. 815, Dept. of Physics, NTU

Abstract:
There has been an extensive series of works aimed at understanding the non-perturbative QFT in AdS and Minkowski spacetime using bootstrap techniques. We take the first step in a non-perturbative approach to QFT in dS.  We derive the Kallen-Lehmann representation of spinning two-point functions and find an inversion formula for the spectral density and discuss its analyticity properties. We conclude by reporting explicit expressions of the spectral density for several examples including CFT and free theory composite operator two-point functions.