Inflation including collapse of the wave function: The quasi-de Sitter case

GABRIEL LEON; LANDAU, SUSANA J.; MARIA PIA PICCIRILLI

EUROPEAN PHYSICAL JOURNAL C - PARTICLES AND FIELDS

SPRINGER

Lugar: Berlin; Año: 2015 vol. 75 p. 1 - 25

1434-6044

The precise physical mechanism describing the emergence of the seeds of cosmic  structure from a perfect isotropic and homogeneous universe has not been fully  explained by the standard version of inflationary  models. To handle this  shortcoming, D. Sudarsky and collaborators have developed a proposal: emph{the  self-induced collapse hypothesis.} In this scheme, the objective collapse of  the inflaton wave function is responsible for the emergence of inhomogeneity  and anisotropy at all scales. In previous papers, the proposal was developed  with an almost exact de Sitter space-time approximation for the background that  led to a perfect scale-invariant power spectrum. In the present article, we  consider a full  quasi-de Sitter expansion and calculate the primordial power  spectrum for three different choices of the self-induced collapse. The  consideration of a quasi-de Sitter background allow us to distinguish  departures from an exact scale-invariant power spectrum that are due to the  inclusion of  the collapse hypothesis. These deviations are also different from  the prediction of standard inflationary models with running spectral index.  Comparison with the primordial power spectrum and the CMB temperature   fluctuation spectrum preferred by the latest observational data is also  discussed. From the analysis performed in this work, it follows that most of  the collapse schemes analyzed in this paper are viable candidates to explain  present observations of the CMB fluctuation spectrum.