We embed a flipped SU(5) × U(1) GUT model in a no-scale supergravity framework, and discuss its predictions for cosmic microwave background observables, which are similar to those of the Starobinsky model of inflation. Measurements of the tilt in the spectrum of scalar perturbations in the cosmic microwave background, ns, constrain significantly the model parameters. We also discuss the model's predictions for neutrino masses, and pay particular attention to the behaviours of scalar fields during and after inflation, reheating and the GUT phase transition. We argue in favor of strong reheating in order to avoid excessive entropy production which could dilute the generated baryon asymmetry.
Bibliographical noteFunding Information:
The work of J.E. was supported in part by the U.K. STFC via the research grant ST/J002798/1. The work of D.V.N. was supported in part by the DOE grant DE-FG02-13ER42020 and in part by the Alexander S. Onassis Public Benefit Foundation. The work of K.A.O. was supported in part by DOE grant DE-SC0011842 at the University of Minnesota. The work of N.N. was supported by the Grant-in-Aid for Scientific Research (No.17K14270).
© 2017 IOP Publishing Ltd and Sissa Medialab.
- baryon asymmetry
- neutrino masses from cosmology
- supersymmetry and cosmology