https://doi.org/10.1140/epjc/s10052-019-6803-7
Regular Article - Theoretical Physics
Emergent inflation from a Nambu–Jona-Lasinio mechanism in gravity with non-dynamical torsion
1
Department of Physics, Center for Field Theory and Particle Physics, Fudan University, Shanghai, 200433, China
2
Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, Taipei, 10617, Taiwan
3
Department of Physics, National Taiwan University, Taipei, 10617, Taiwan
4
Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory, Stanford University, Stanford, CA, 94305, USA
* e-mail: marciano@fudan.edu.cn
Received:
29
November
2018
Accepted:
20
March
2019
Published online:
2
April
2019
We discuss how inflation can emerge from a four-fermion interaction induced by torsion. Inflation can arise from coupling torsion to Standard Model fermions, without any need of introducing new scalar particles beyond the Standard Model. Within this picture, the inflaton field can be a composite field of the SM-particles and arises from a Nambu–Jona-Lasinio mechanism in curved space-time, non-minimally coupled with the Ricci scalar. The model we specify predicts small value of the r-parameter, namely 
, which nonetheless would be detectable by the next generation of experiments, including BICEP 3 and the AliCPT projects.
© The Author(s), 2019
