XIIIth School of Cosmology
November 12 - 18, 2017IESC, Cargèse
The CMB from A to Z
promises and challenges of the CMB as a cosmological probe

A GW yielding small field model

Ira Wolfson
Ben-Gurion Univ. of the Negev

Short Talk

Abstract :Small field models of inflation have previously thought to be disfavored by the CMB data, in the context of gravitational wave (GW) signal generation. Ben-Dayan and Brustein have introduced models that, contrary to popular wisdom, are able to to yield significant GW signature, while conforming to known CMB observables (2010). While based on solid arguments, the work presented, shows the model building technique used by Ben-Dayan, Brustein and others, to rely on ill-suited assumptions. These assumptions are codified in the Stewart-Lyth analytic expression (1993), which is commonly used. The work presented shows these to break due to e-fold hierarchy breakdown and other issues. Additionally, we find new small field candidates of the Ben-Dayan&Brustein variety that are precisely calculated and yield r=0.001 while conforming to known CMB observables, thus reviving the model.