2005/10/31 by A. Yoshisato, Ayako Yoshisato, Masahiro Morikawa +5 · 21 citations
Physics and Astronomy · #Computational astrophysics #Cosmology and Gravitation Theories #Curse of dimensionality #Gravitation #Gravitational collapse #Noncommutative and Quantum Gravity Theories #Order (exchange) #Pulsars and Gravitational Waves Research #Work (physics) #astro-ph
paper · pdf · doi:10.1086/498496
published in The Astrophysical Journal 637(2), 555-560 (IOP Publishing) · 16 pages, to appear in The Astrophysical Journal
arxiv created 2005/12/24 · openalex publication_date 2006/01/25 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Why does the Zel'dovich approximation (ZA) work well to describe gravitational collapse in the universe? This problem is examined by focusing on its dependence on the dimensionality of the collapse. The ZA is known to be exact for a one-dimensional collapse. We show that the ZA becomes progressively more accurate in the order of three-, two-, and one-dimensional collapses. Furthermore, using models for spheroidal collapse, we show that the ZA remains accurate in all collapses, which become progressively lower dimensional with the passage of time. That is, the ZA is accurate because the essence of the gravitational collapse is incorporated in the ZA.