BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//talks.cam.ac.uk//v3//EN
BEGIN:VTIMEZONE
TZID:Europe/London
BEGIN:DAYLIGHT
TZOFFSETFROM:+0000
TZOFFSETTO:+0100
TZNAME:BST
DTSTART:19700329T010000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:+0100
TZOFFSETTO:+0000
TZNAME:GMT
DTSTART:19701025T020000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
CATEGORIES:DAMTP Friday GR Seminar
SUMMARY:Resonant non-Gaussianity - Enrico Pajer\, Cornell
DTSTART;TZID=Europe/London:20100514T130000
DTEND;TZID=Europe/London:20100514T140000
UID:TALK24131AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/24131
DESCRIPTION:Two of the most exciting observables in the cosmic
  microwave background (CMB) radiation\, which coul
 d deeply impact our picture of the early universe\
 , are non-Gaussianity and tensor modes. A potentia
 l detection of tensor modes can be explained in te
 rms of a model of large field inflation. Theoretic
 al considerations suggest that a symmetry should b
 e invoked in order to protect the flatness of the 
 inflaton potential and hence an axion enjoying a s
 hift symmetry is a natural candidate. As main exam
 ple\, I will present a model of inflation in strin
 g theory based on axion monodromy. Non-perturbativ
 e effects typically correct the axion potential le
 ading to small sinusoidal modulations on top of an
  otherwise flat slow roll potential. It can be sho
 wn analytically that a resonance between the oscil
 lations of the background and the oscillations of 
 the curvature fluctuations is responsible for the 
 production of an observably large non-Gaussian sig
 nal. An explicit expression for the shape of this 
 resonant non-Gaussianity is presented. There is es
 sentially no overlap between this shape and the lo
 cal\, equilateral\, and orthogonal shapes\, and in
  fact resonant non-Gaussianity is not captured by 
 the simplest version of the effective field theory
  of inflation. Hopefully the analytic expression f
 or resonant non-Gaussianity will be useful to furt
 her observationally constrain this class of models
 .
LOCATION:Pavilion B Potter Room (B1.19)
CONTACT:James Fergusson
END:VEVENT
END:VCALENDAR