Master defense by Song Chen 2011-10-12 – University of Copenhagen

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Master defense by Song Chen 2011-10-12

Anomalous parity asymmetry of the CMB  

The symmetry test of Cosmic Microwave Background(CMB) anisotropy is
one of the fundamental test of the properties of the space and time at large
scale. In this thesis, I have reviewed the investigations of parity asymmetry
in the CMB anisotropy, and propose a new test based on the analysis
of the morphology of the CMB map through the spectral parameters of
CMB fluctuation. Combined with simulations, our morphological parity
test shows a significant difference of the even parity symmetry from the
theoretical expectations. The results well agree that even parity map possesses
an anomalous at 2-in-1000 level. The morphological analyses also
imply that the theoretical even parity sky is smoother than the observed
map. Since the previous investigations ruled out various non-cosmological
origins, in this thesis I will focus on a possible cosmological primordial origin,
i.e. the non-trivial topology model. In our investigation, the half-turn
topology universe suggests that the odd parity preference could be obtained
by choosing appropriate position of observer. The further discrimination
between those possible origins would be given by the PLANK data. The
PLANK surveyor with entirely different design and higher accuracy devices
will probably greatly help us to
find out the origin.

Supervisor: Pavel Naselsky