Astronomy and Astrophysics – Astrophysics
Scientific paper
1992-08-27
Phys.Lett. B291 (1992) 391-398
Astronomy and Astrophysics
Astrophysics
Scientific paper
10.1016/0370-2693(92)91393-N
We analyse the implications for inflationary models of the cosmic microwave background (cmb) anisotropy measured by COBE. Vacuum fluctuations during inflation generate an adiabatic density perturbation, and also gravitational waves. The ratio of these two contributions to the cmb anisotropy is given for an arbitrary slow-roll inflaton potential. Results from the IRAS/QDOT and POTENT galaxy surveys are used to normalise the spectrum of the density perturbation on the scale $20h^{-1}\Mpc$, so that the COBE measurement on the scale $10^3h^{-1}\Mpc$ provides a lower bound on the spectral index $n$. For `power law' and `extended' inflation, gravitational waves are significant and the bound is $n>0.84$ at the $2$-sigma level. For `natural' inflation, gravitational waves are negligible and the constraint is weakened to $n>0.70$, at best marginally consistent with a recent proposal for explaining the excess clustering observed in the APM galaxy survey. Many versions of extended inflation, including those based on the Brans--Dicke theory, are ruled out, because they require $n\lsim 0.75$ in order that bubbles formed at the end of inflation should not be observed now in the cmb.
Liddle Andrew R.
Lyth David H.
No associations
LandOfFree
COBE, Gravitational Waves, Inflation and Extended Inflation does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with COBE, Gravitational Waves, Inflation and Extended Inflation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and COBE, Gravitational Waves, Inflation and Extended Inflation will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-701965