Observational constraints on inflationary potentials within the quantum collapse framework

Abstract

The physical mechanism responsible for the emergence of primordial cosmic seeds from a perfect isotropic and homogeneous Universe has not been fully addressed in standard cosmic inflation. To handle this shortcoming, D. Sudarsky et al have developed a proposal: the self-induced collapse hypothesis. In this scheme, the objective collapse of the inflaton's wave function generates the inhomogeneity and anisotropy at all scales. In this paper we analyze the viability of a set of inflationary potentials in both the context of the collapse proposal and within the standard inflationary framework. For this, we perform a statistical analysis using recent CMB and BAO data to obtain the prediction for the scalar spectral index $n_s$ in the context of a particular collapse model: the Wigner scheme. The predicted $n_s$ and the tensor-to-scalar ratio $r$ in terms of the slow roll parameters is different between the collapse scheme and the standard inflationary model. For each potential considered we compare the prediction of $n_s$ and $r$ with the limits established by observational data in both pictures. The result of our analysis shows in most cases a difference in the inflationary potentials allowed by the observational limits in both frameworks. In particular, in the standard approach the more concave a potential is, the more is favored by the data. On the other hand, in the Wigner scheme, the data favors equally all type of concave potentials, including those at the border between convex and concave families.