Behavior of three-point functions in inflationary and bouncing scenarios

Inflation has been widely regarded as the most promising scenario to explain our observations of the early universe. However, in view of the difficulties associated with arriving at a unique model of inflation, it seems worthwhile to investigate alternative scenarios of the early universe, specifically the so-called bouncing models. In this talk, I shall discuss the evaluation of three-point functions in a specific inflationary model and a particular class of bouncing models in order to illustrate the primary differences that can arise between these two scenarios at the level of the three-point functions. I shall consider the axion monodromy model of inflation, which involves a canonical scalar field that is governed by a linear potential with superimposed modulations. I shall discuss the evaluation of the scalar-scalar-tensor cross-correlation in this model and analytically establish the consistency relation (in the squeezed limit) for this three-point function. I shall then consider a specific class of bouncing models, namely the matter bounce scenario, and discuss the analytical evaluation of the tensor modes and the tensor bispectrum in this scenario. Further, I shall show that the consistency relation corresponding to the tensor bispectrum is violated in the matter bounce. The behavior of the non-Gaussianities, specifically the three-point functions, generated in the inflationary and bouncing scenarios can hence be used to compare and contrast between the predictions of these alternative models of the early universe.
 

Dates: 

Tuesday, 25 April, 2017 - 14:00

Salle / Local: 

646 A - Mondrian

Nom/Prénom // Last name/First name: 

Debika Chowdhury

Affiliation: 

Department of Physics, Indian Institute of Technology Madras, Chennai, India

Equipe organisatrice / Organizing team: 

  • Théorie