2003/10/31 by Shin'ichi Nojiri, Christian Knigge, CHRISTIAN KNIGGE +1 · 2 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph #gr-qc #hep-th
paper · pdf · doi:10.1142/s0217732304015282
published as Mod.Phys.Lett.A19:1273-1280,2004 · LaTeX file, 10 pages, references are added
arxiv created 2003/11/10 · openalex publication_date 2004/08/30 · arxiv updated 2009/12/01 · openalex created_date 2019/06/27 · openalex updated_date 2026/07/28
One possibility to explain the current accelerated expansion of the universe may be related with the presence of cosmologically evolving scalar whose mass depends on the local matter density (chameleon cosmology). We point out that matter quantum effects in such scalar-tensor theory produce the chameleon scalar field dependent conformal anomaly. Such conformal anomaly adds higher derivative terms to chameleon field equation of motion. As a result, the principal possibility for instabilities appears. These instabilities seem to be irrelevant at small curvature but may become dangerous in the regions where gravitational field is strong.