Conceptual Problems of Inflationary Cosmology and a New Approach to Cosmological Structure Formation

@article{Brandenberger2007ConceptualPO,
  title={Conceptual Problems of Inflationary Cosmology and a New Approach to Cosmological Structure Formation},
  author={Robert Brandenberger},
  journal={Lecture Notes in Physics},
  year={2007},
  volume={738},
  pages={393-424}
}
In spite of its great phenomenological success, current models of scalar field-driven inflation suffer from important unresolved conceptual issues. New fundamental physics will be required to address these questions. String theory is a candidate for a unified quantum theory of all four forces of nature. As will be shown, string theory may lead to a cosmological background quite different from an inflationary cosmology, and may admit a new stringy mechanism for the origin of a roughly scale… 

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