2008/06/30 by F. R. Klinkhamer, G. E. Volovik · 3 citations
Physics and Astronomy · #Amplitude #Black Holes and Theoretical Physics #Classical mechanics #Cosmological constant #Cosmology #Cosmology and Gravitation Theories #Dark energy #De Sitter universe #Gravitation #Inflation (cosmology) #Mathematical physics #Metric expansion of space #Physics #Quantum mechanics #Relativity and Gravitational Theory #Scale factor (cosmology) #Theoretical physics #Universe #Vacuum energy #Zero-energy universe #astro-ph #gr-qc #hep-th
paper · pdf · doi:10.1103/physrevd.78.063528
published as Phys.Rev.D78:063528,2008 · 24 (not 25) pages, v7(=v6 with latex problem corrected): published version in preprint style
openalex publication_date 2008/09/15 · arxiv created 2008/09/18 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
A modified-gravity theory is considered with a four-form field strength F, a variable gravitational coupling parameter G(F), and a standard matter action. This theory provides a concrete realization of the general vacuum variable q as the four-form amplitude F and allows for a study of its dynamics. The theory gives a flat Friedmann-Robertson-Walker universe with rapid oscillations of the effective vacuum energy density (cosmological ``constant''), whose amplitude drops to zero asymptotically. Extrapolating to the present age of the Universe, the order of magnitude of the average vacuum energy density agrees with the observed near-critical vacuum energy density of the present universe. It may even be that this type of oscillating vacuum energy density constitutes a significant part of the so-called cold dark matter in the standard Friedmann-Robertson-Walker framework.