A Friedman cosmology is investigated based on scalar-tensor gravitation with general metric coupling and scalar potential functions. We show that for a broad class of such functions, the scalar field can be dynamically trapped using a recently suggested mechanism. The trapped scalar can drive inflation and accelerated cosmic expansion, compatible with standard requirements. The inflationary phase admits a natural exit with a value of the Hubble parameter dictated by the duration of inflation in a parameter independent manner. For inflationary duration consistent with the GUT description, the resulting Hubble parameter is found to be consistent with its observed value.
- Modified theories of gravity
- cosmic inflation
- dark energy
Wang, C. H-T., Reid, J. A., St J. Murphy, A., De Paula Farias Rodrigues, D., Al-Alawi, M., Bingham, R., ... Davies, T. B. (2016). A consistent scalar-tensor cosmology for inflation, dark energy and the Hubble parameter. Physics Letters A, 380(45), 3761-3765. https://doi.org/10.1016/j.physleta.2016.09.038