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The History of Cosmological Star Formation: Three Independent Approaches and a Critical Test Using the Extragalactic Background Light

Taking three independent approaches, we investigate the simultaneous constraints set on the cosmic star formation history from various observations, including stellar mass density and extragalactic background light (EBL). We compare results based on: (1) direct observations of past light-cone, (2) a model using local fossil evidence constrained by SDSS observations at z ~ 0 (the "Fossil" model), and (3) theoretical ab initio models from three calculations of cosmic star formation history: (a) new 10243 total variation diminishing (TVD) cosmological hydrodynamic simulation, (b) analytic expression of Hernquist & Springel based on cosmological smoothed particle hydrodynamics (SPH) simulations, and (c) semianalytic model of Cole et al. We find good agreement among the three independent approaches up to the order of observational errors, except that all the models predict bolometric EBL of Itot ≃ 37 - 52 nW m-2 sr-1, which is at the lower edge of the observational estimate by Hauser & Dwek. We emphasize that the Fossil model that consists of two components—spheroids and disks—when normalized to the local observations, provides a surprisingly simple but accurate description of the cosmic star formation history and other observable quantities. Our analysis suggests that the consensus global parameters at z = 0 are Ω⋆ = 0.0023 ± 0.0004, IEBL = 43 ± 7 nW m-2 sr-1, = × 10-2 M☉ yr-1 Mpc-3, jbol = × 108 L☉ Mpc-3.