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VERSION:2.0
CALSCALE:GREGORIAN
PRODID:UW-Physics-TWaP
BEGIN:VEVENT
SEQUENCE:1
UID:UW-Physics-Event-5155
DTSTART:20190821T190000Z
DTEND:20190821T201500Z
DTSTAMP:20200410T072731Z
LAST-MODIFIED:20190820T211453Z
LOCATION:5280 Chamberlin
SUMMARY:Quantum non-linear evolution of inflationary tensor perturbations\, Theory Seminar (High Energy/Cosmology)\, Jinn-Ouk Gong\, KASI
DESCRIPTION: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.
URL:https://wp.physics.wisc.edu/twap/?id=5155
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