Can the universe afford inflation

@article{Albrecht2004CanTU,
  title={Can the universe afford inflation},
  author={Andreas Albrecht and Lorenzo del Sorbo},
  journal={Physical Review D},
  year={2004},
  volume={70},
  pages={063528}
}
Cosmic inflation is envisioned as the 'most likely' start for the observed universe. To give substance to this claim, a framework is needed in which inflation can compete with other scenarios and the relative likelihood of all scenarios can be quantified. The most concrete scheme to date for performing such a comparison shows inflation to be strongly disfavored. We analyze the source of this failure for inflation and present an alternative calculation, based on more traditional semiclassical… 

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