On Primordial Density Perturbation and Decaying Speed of Sound
arXiv:0807.3226 · doi:10.1103/PhysRevD.79.067301
Abstract
The decaying speed of sound can lead to the emergence of the primordial density perturbation in any expanding phase, even if the expansion is decelerated. Recently, some proposals have been given to implement this mechanism, in which it was found that the primordial spectrum of scalar perturbation can be scale invariant. In this note, we will give more insights for the details of this seeding mechanism.
3 pages, 2 eps figure, contents extended, refs. added, published version,
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Cited by in corpus (5)
- DBI Realizations of the Pseudo-Conformal Universe and Galilean Genesis Scenarios
- Scale Invariance via a Phase of Slow Expansion
- Oscillating modulation to B-mode polarization from varying propagating speed of primordial gravitational waves
- AdS cycles in eternally inflating background
- Adiabatic Duality: Duality of cosmological models with varying slow-roll parameter and sound speed