Figure 1: Left panel: The potential as a function of ( α ) and ( β ) components of the field X . Note the nearly flat direction ( β ) that we use for our inflationary trajectories. Graceful exit and particle creation occurs in the non-linear part of the X field. Right panel: WMAP5 cosmological constraints (yellow region) in the r − n$_{S}$ plane. For no-fine-tuned minimal inflation models the green and red area show our predictions for both cases of a stable (concave) potential and unstable (convex) potential. The Planck satellite will be able to provide significantly tigther constraints on r and especially n$_{S}$ (at the < 0 . 5% level) thus further constraining our model. The dashed line is the limit in r that can be achieved with an ideal CMB polarization experiment [14] These are bonuses which come directly from the observa- tions of the initial density perturbations from WMAP data [11]. The fact that the inflaton is lighter than the gravitino may have interesting low-energy phenomenological impli- cations. Furthermore in this simple model it is easy to obtain sufficient number of efoldings with moderate values of the η parameter. To explore our proposal in more detail, it is important to construct an explicit model, even if not very realistic, in order to understand in more detail the end of inflation, the reheating mechanisms, and also the fine structure of the inflaton potential. We hope to report on this in the near future [25]. We would like to thank G. Dvali, G. Giudice, J. Les- gourgues, S. Matarrese, G. Ross, Nathan Seiberg, M.A. V´ azquez Mozo, and L. Verde for useful discussion. C.G. and R.J. would like to thank the CERN Theory Group for hospitality while part of this work was done. Acknowledgements References [1] Guth A. H., 1981, PRD, 23, 347 [2] Mukhanov V. F., Chibisov G. V., 1981, ZhETF Pis ma Redak- tsiiu, 33, 549 [3] Sato K., 1981, MNRAS, 195, 467 [4] Albrecht A., Steinhardt P. J., 1982, Physical Review Letters, 48, 1220 [5] Guth A. H., Pi S.-Y., 1982, Physical Review Letters, 49, 1110 [6] Hawking S. W., 1982, Physics Letters B, 115, 295 [7] Linde A. D., 1982, Physics Letters B, 108, 389 [8] Starobinsky A. A., 1982, Physics Letters B, 117, 175 [9] Bardeen J. M., Steinhardt P. J., Turner M. S., 1983, PRD, 28, 679 [10] Verde L., Peiris H., 2008, JCAP, 7, 9 [11] Komatsu E., et al., 2009, ApJS, 180, 330 [12] Peiris H., verde L., 2009, arXiv0912.0268 [13] Liddle A. R., Lyth D. H., 1992, PhLB, 291, 391 [14] Verde L., Peiris H. V., Jimenez R., 2006, JCAP, 1, 19 [15] Verde L., Jimenez R., Kamionkowski M., Matarrese S., 2001, MNRAS, 325, 412 [16] Kolb E. W., Turner M. S., 1990, The Early Universe, Addison Wesley. [17] Mukhanov, S, 2005, Physical Foundations of Cosmology, Cam- bridge University Press. [18] J. R. Ellis, D. V. Nanopoulos, K. A. Olive and K. Tamvakis, Phys. Lett. B 118 , 335 (1982). [19] B. A. Ovrut and P. J. Steinhardt, Phys. Lett. B 133 , 161 (1983), 7