2007/04/30 by A. Bilandzic, Ante Bilandzic, Tomislav Prokopec · 6 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Particle physics theoretical and experimental studies #astro-ph
paper · pdf · doi:10.1103/physrevd.76.103507
published as Phys.Rev.D76:103507,2007 · 31 pages, 2 eps figures, references added and an improved introduction
arxiv created 2007/05/17 · openalex publication_date 2007/11/05 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We consider the nonminimally coupled \ensuremathλ\ensuremathφ4 scalar field theory in de Sitter space and construct the renormalization group improved renormalized effective theory at the one-loop level. Based on the corresponding quantum Friedmann equation and the scalar field equation of motion, we calculate the quantum radiative corrections to the scalar spectral index ns, gravitational wave spectral index ng, and the ratio r of tensor-to-scalar perturbations. When compared with the standard (tree-level) values, we find that the quantum contributions are suppressed by \ensuremathλN2, where N denotes the number of e-foldings. Hence, there is an N2 enhancement with respect to the naive expectation, which is due to the infrared enhancement of scalar vacuum fluctuations characterizing de Sitter space. Since observations constrain \ensuremathλ to be very small \ensuremathλ\ensuremath∼10^\ensuremath-12 and N\ensuremath∼50--60, the quantum corrections in this inflationary model are unobservably small.