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SUMMARY:Perfect bounce in quantum cosmology - Steffen Gielen (Imperial)
DTSTART:20160129T130000Z
DTEND:20160129T140000Z
UID:TALK62946@talks.cam.ac.uk
CONTACT:43345
DESCRIPTION:A detailed analysis of a quantum cosmological model based on g
 eneral relativity coupled to conformal matter (a perfect radiation fluid a
 nd conformally coupled scalars) is presented\, which shows how the univers
 e undergoes a nonsingular "perfect bounce". This bounce can be described b
 y a path in the complex plane for the scale factor\, similar to a well-kno
 wn description of quantum tunnelling in complex time. In the case of FRW s
 ymmetry\, the path integral and transition amplitudes can be computed exac
 tly. For an anisotropic Bianchi I model\, we give the general solution to 
 the Wheeler-DeWitt equation and show how to define global positive- and ne
 gative-frequency modes which interpolate smoothly between negative and pos
 itive infinity\, again encountering no singular behaviour at the "Big Bang
 ". Partial results on nonlinear perturbations suggest that the picture can
  be extended to more general inhomogeneous universes.
LOCATION:Pavilion B Potter Room (B1.19)
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