2002/11/30 by James M. Cline, Jérémie Vinet · 2 citations
Physics and Astronomy · #Acceleration #Astrophysics #Black Holes and Theoretical Physics #Classical mechanics #Computer science #Constant (computer programming) #Cosmology #Cosmology and Gravitation Theories #Dark energy #Energy (signal processing) #Metric expansion of space #Physics #Quantum mechanics #Relativity and Gravitational Theory #Statistical physics #Universe #astro-ph #hep-ph #hep-th
paper · pdf · doi:10.1103/physrevd.68.025015
published as Phys.Rev. D68 (2003) 025015 · 8 pages, minor changes. To appear in Physical Review D
arxiv created 2003/05/29 · openalex publication_date 2003/07/16 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
It has recently been proposed that the Universe might be accelerating as a consequence of extra dimensions with time-varying size. We show that, although these scenarios can lead to acceleration, they run into serious difficulty when taking into account the limits on the time variation of the four-dimensional Newton constant. On the other hand, models of ``Cardassian'' expansion based on extra dimensions which have been constructed so far violate the weak energy condition for the bulk stress energy, for parameters that give an accelerating Universe.