Abstarct
The recent Planck satellite combined with earlier results eliminate a wide spectrum of more complex inflationary models and favor models with a single scalar field, as reported in the analysis of the collaboration. More important, though, is that all the simplest inflaton models are disfavored by the data while the survivingmodels – namely, those with plateau-like potentials – are problematic. We discuss how the restriction to plateau-like models leads to three independent problems: it exacerbates both the initial conditions problem and the multiverse-unpredictability problem and it creates a new difficulty which we call the inflationary “unlikeliness problem.” Finally, we comment on problems reconciling inflation with a standard model Higgs, as suggested by recent LHC results. In sum, we find that recent experimental data disfavors all the best-motivated inflationary scenarios and introduces new, serious difficulties that cut to the core of the inflationary paradigm. Forthcoming searches for B-modes, non-Gaussianity and new particles should be decisive
Contents
1. Which inflationary models survive after Planck2013?
2. How do plateau-like inflationary models affect the initial conditions problem?
3. Is a plateau-like potential likely according to the inflationary paradigm?
4. Is Planck2013 data compatible with the multiverse?
5. Is there any escape from these new problems?
6. More trouble for inflation from the LHC?
7. Discussion