2000/02/28 by M. Joyce, Michael Joyce, Philip W. Anderson +5
Physics and Astronomy · #Advanced Mathematical Theories and Applications #Anisotropy #Astrophysics #Cosmic background radiation #Cosmic microwave background #Cosmological principle #Cosmology #Cosmology and Gravitation Theories #Dark energy #Dark matter #Fractal #Galaxies: Formation, Evolution, Phenomena #Galaxy #Homogeneity (statistics) #Metric expansion of space #Non-standard cosmology #Observational cosmology #Physics #Quantum mechanics #Structure formation #Theoretical physics #Universe #astro-ph #cond-mat #gr-qc #hep-ph
paper · pdf · doi:10.1209/epl/i2000-00285-3
published as Europhys.Lett. 49 (2000) 416-422 · 7 pages, no figures, to appear in Europhysics Letters
arxiv created 2000/02/28 · openalex publication_date 2000/05/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The clustering of galaxies is well characterized by fractal properties, with the presence of an eventual cross-over to homogeneity still a matter of considerable debate. In this letter we discuss the cosmological implications of a fractal distribution of matter, with a possible cross-over to homogeneity at an undetermined scale R homo . Contrary to what is generally assumed, we show that, even when R homo → ∞ , this possibility can be treated consistently within the framework of the expanding universe solutions of Friedmann. The fractal is a perturbation to an open cosmology in which the leading homogeneous component is the cosmic background radiation (CBR). This cosmology, inspired by the observed galaxy distributions, provides a simple explanation for the recent data which indicate the absence of deceleration in the expansion ( q 0 ≈ 0). Correspondingly the "age problem" is also resolved. Further we show that the model can be extended back from the curvature-dominated arbitrarily deep into the radiation-dominated era, and we discuss qualitatively the modifications to the physics of the anisotropy of the CBR, nucleosynthesis and structure formation.