Does Gravity's Rainbow induce Inflation without an Inflaton?
  We study aspects of quantum cosmology in the presence of a modified space-time geometry. In particular, within the context of Gravity's Rainbow modified geometry, motivated from quantum gravity corrections at the Planck energy scale, we show that the distortion of the metric leads to a Wheeler-De Witt equation whose solution admits outgoing plane waves. Hence, a period of cosmological inflation may arise without the need for introducing an inflaton field. 
Remo Garattini and Mairi Sakellariadou
gr-qc hep-th