Scale-invariant alternatives to general relativity. III. The inflation-dark energy connection

  title={Scale-invariant alternatives to general relativity. III. The inflation-dark energy connection},
  author={Santiago Casas and Georgios K Karananas and Martin Pauly and Javier Rubio},
  journal={Physical Review D},
We discuss the cosmological phenomenology of biscalar-tensor models displaying a maximally symmetric Einstein-frame kinetic sector and constructed on the basis of scale symmetry and volume-preserving diffeomorphisms. These theories contain a single dimensionful parameter Λ0—associated with the invariance under the aforementioned restricted coordinate transformations—and a massless dilaton field. At large field values these scenarios lead to inflation with no generation of isocurvature… Expand

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