the Starobinsky model
Based on arXiv:1507.04344 [hep-th] with T. Asaka, S. Iso, H. Kawai, K. Kohri, T. Noumi.
The 27th International Symposium on Lepton Photon Interactions at High Energies, Ljubljana, Slovenia, August 21, 2015
P. A. R. Ade et al. [Planck Collaboration], "Planck 2015 results. XX. Constraints on inflation", arXiv:1502.02114 [astro-ph.CO].
Peculiar Form of the Action
1. Scale invariance
2. Extra dimensions
Higher dimensional action
Tuning one parameter
(in addition to the cosmological constant)
- Starobinsky model has a peculiar form of the action.
If the deviation is observed, it implies the fundamental scale,
- It may be originated from extra dimensions.
- One tuning is needed to be consistent with data.
Reinterpretation of the Starobinsky model
By Takahiro Terada