Marco Bruni
GGI Florence, October 2006
Perturbations of IS
§For
standard linear EoS P = w r, these variables diverge at the singularity, signaling anisotropy.
§For P= ar + r /rc , after
splitting in scalar vector and tensor modes, we find that all the expansion normalised perturbations vanish at the singularity, as we found in the brane case.
§As in the
brane case, the r term makes the singularity isotropic, dominating over shear.
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