1997/11/07 by Neta A. Bahcall, Bahcall, Neta A.
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #Cosmology and Gravitation Theories #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9711062
12 pages, 3 figures, Review talk presented at the 12 th Postdam Cosmology Workshop, "Large Scale Structure: Tracks and Traces", World Scientific 1998
openalex publication_date 1997/11/07 · arxiv created 1997/11/09 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Clusters of galaxies, the most massive virialized systems known, provide a powerful tool for studying the structure, the mass density, and the cosmology of our universe. Clusters furnish one of the best estimates of the dynamical mass density parameter on 1 Mpc scale, Ωdyn; the best measure of the baryon density fraction in the universe; an excellent tracer of the large-scale structure of the universe; and, most recently, a powerful tracer of the evolution of structure in the universe and its unique cosmological implications. I review the above measures and show that they portray a consistent picture of the universe and place stringent constraints on cosmology. Each of these independent measures suggests a low-density universe, Ωm ≃ 0.3 ± 0.1, with mass approximately tracing light on large scales.