https://doi.org/10.1140/epjc/s10052-016-4390-4
Regular Article - Theoretical Physics
From stable to unstable anomaly-induced inflation
1
Departamento de Física, ICE, Universidade Federal de Juiz de Fora, Campus Universitário, Juiz de Fora, MG, 36036-330, Brazil
2
Departamento de Física, CFM, Universidade Federal de Santa Catarina, Bairro da Trindade, Caixa Postal 476, Florianópolis, SC, 88040-970, Brazil
3
Tomsk State Pedagogical University and Tomsk State University, Tomsk, Russia
4
L. D. Landau Institute for Theoretical Physics RAS, Moscow, 119334, Russia
5
Department of Physics and Astronomy, Institute for Theoretical Physics, Utrecht University, 3508 TD, Utrecht, The Netherlands
* e-mail: shapiro@fisica.ufjf.br
Received:
5
October
2015
Accepted:
20
September
2016
Published online:
6
October
2016
Quantum effects derived through conformal anomaly lead to an inflationary model that can be either stable or unstable. The unstable version requires a large dimensionless coefficient of about 
in front of the 
term that results in the inflationary regime in the 
(“Starobinsky”) model being a generic intermediate attractor. In this case the non-local terms in the effective action are practically irrelevant, and there is a ‘graceful exit’ to a low curvature matter-like dominated stage driven by high-frequency oscillations of R – scalarons, which later decay to pairs of all particles and antiparticles, with the amount of primordial scalar (density) perturbations required by observations. The stable version is a genuine generic attractor, so there is no exit from it. We discuss a possible transition from stable to unstable phases of inflation. It is shown that this transition is automatic if the sharp cut-off approximation is assumed for quantum corrections in the period of transition. Furthermore, we describe two different quantum mechanisms that may provide a required large -term in the transition period.
© The Author(s), 2016
