Density fluctuations in a {kappa}-deformed inflationary universe
- Department of Physics, Yonsei University, Seoul 120-749 (Korea, Republic of)
We study the spectrum of metric fluctuation in {kappa}-deformed inflationary universe. We write the theory of scalar metric fluctuations in the {kappa}-deformed Robertson-Walker space, which is represented as a nonlocal theory in the conventional Robertson-Walker space. One important consequence of the deformation is that the mode generation time is naturally determined by the structure of the {kappa}-deformation. We expand the nonlocal action in H{sup 2}/{kappa}{sup 2}, with H being the Hubble parameter and {kappa} the deformation parameter, and then compute the power spectra of scalar metric fluctuations both for the cases of exponential and power law inflations up to the first order in H{sup 2}/{kappa}{sup 2}. We show that the power spectra of the metric fluctuation have nontrivial corrections on the time dependence and on the momentum dependence compared to the commutative space results. Especially for the power law inflation case, the power spectrum for UV modes is weakly blueshifted early in the inflation and its strength decreases in time. The power spectrum of far-IR modes has cutoff proportional to k{sup 3} which may explain the low cosmic microwave background (CMB) quadrupole moment.
- OSTI ID:
- 20711550
- Journal Information:
- Physical Review. D, Particles Fields, Vol. 72, Issue 10; Other Information: DOI: 10.1103/PhysRevD.72.103523; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
- Country of Publication:
- United States
- Language:
- English
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