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Cosmological Density Perturbations From A Quantum Gravitational Model Of Inflation

L. R. Abramo·N. C. Tsamis·R. P. Woodard
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Abstract

We derive the implications for anisotropies in the cosmic microwave background following from a model of inflation in which a bare cosmological constant is gradually screened by an infrared process in quantum gravity. The model predicts that the amplitude of scalar perturbations is $A_S = (2.0 \pm .2) \times 10^{-5}$, that the tensor-to-scalar ratio is $r \approx 1.7 \times 10^{-3}$, and that the scalar and tensor spectral indices are $n \approx .97$ and $n_T \approx -2.8 \times 10^{-4}$, respectively. By comparing the model's power spectrum with the COBE 4-year RMS quadrupole, the mass scale of inflation is determined to be $M = (.72 \pm .03) \times 10^{16}~{\rm GeV}$. At this scale the model produces about $10^8$ e-foldings of inflation, so another prediction is $Ω= 1$.

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L. R. Abramo, N. C. Tsamis, R. P. Woodard. 1998-03-16. Cosmological Density Perturbations From A Quantum Gravitational Model Of Inflation. https://doi.org/10.1002/(sici)1521-3978(199904)47%3A4%3C389%3A%3Aaid-prop389%3E3.0.co%3B2-d

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