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CATEGORIES:DAMTP Friday GR Seminar
SUMMARY:Towards the exact de Sitter S-matrix of the Princi
pal Chiral Model - Ian Morrison (DAMTP)
DTSTART;TZID=Europe/London:20130524T130000
DTEND;TZID=Europe/London:20130524T140000
UID:TALK44526AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/44526
DESCRIPTION:In Minkowski space the S-matrix in an invaluable t
ool for analysing quantum field theories. Scatteri
ng matrices may also be constructed and exploited
in eternally inflating spacetimes. In the first pa
rt of this talk I will review the perturbative con
struction of the S-matrix in global de Siter space
. I will emphasize itâ€™s value as a gauge and field
redefinition-invariant probe for QFTs in the infl
ationary setting. As time allows I will also discu
ss features of such QFTs which\, while obscure fro
m the vantage point of local correlation functions
\, are transparent when viewed through the S-matri
x.\n\nIn the second part of my talk I will discuss
recent progress towards constructing the exact S-
matrix of the Principal Chiral Model (PCM) in de S
itter space. The PCM is a 2-dimensional non-linear
sigma model endowed with many of the mature attri
butes of QCD\, including asymptotic freedom and di
mensional transmutation. The PCM also contains an
infinite number of hidden symmetries which make th
e theory integrable in Minkowski space. A sufficie
nt number of these symmetries exist also in the de
Sitter theory\, and thus the de Sitter S-matrix m
ay be determined up to a CDD-type ambiguity.
LOCATION:Pavilion B Potter Room (B1.19)
CONTACT:Dr Joan Camps
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