This Week at Physics

<< August 2019 >>
Sun Mon Tue Wed Thu Fri Sat
   1   2   3 
 4   5   6   7   8   9   10 
 11   12   13   14   15   16   17 
 18   19   20   21   22   23   24 
 25   26   27   28   29   30   31 
Add an Event Edit This Event

This Week at Physics

<< Spring 2019 Fall 2019 Spring 2020 >>
Subscribe your calendar or receive email announcements of events

Event Number 5155

  Wednesday, August 21st, 2019

Theory Seminar (High Energy/Cosmology)
Quantum non-linear evolution of inflationary tensor perturbations
Time: 2:00 pm
Place: 5280 Chamberlin
Speaker: Jinn-Ouk Gong, KASI
Abstract: We study the quantum mechanical evolution of the tensor perturbations during inflation with non-linear tensor interactions. We first obtain the Lindblad terms generated by non-linear interactions by tracing out unobservable sub-horizon modes. Then we calculate explicitly the reduced density matrix for the super-horizon modes, and show that the probability of maintaining the unitarity of the squeezed state decreases in time. The decreased probability is transferred to other elements of the reduced density matrix including off-diagonal ones, so the evolution of the reduced density matrix describes the quantum-to-classical transition of the tensor perturbations. This is different from the classicality accomplished by the squeezed state, the suppression of the non-commutative effect, which is originated from the quadratic, linear interaction, and also maintains the unitarity. The quantum-to-classical transition occurs within 5 - 10 e-folds, faster than the curvature perturbation.
Host: Alex Cole
Add this event to your calendar
©2013 Board of Regents of the University of Wisconsin System