The Cosmic Energy Inventory : Construction and Consistency Investigations

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The two noteworthy findings, among others, are that(i) the mass of galaxies is distributed far away to the distance beyond the gravitational binding radius(virial radius), and(ii) a significant amount of dust is present outside galaxies, i. e., dust produced in stars in galaxies is blown out even to the distance beyond the galactic haloes. These mean that the universe is not empty anywhere.Weak gravitational lensing, when applied to large galaxy-quasar samples, leads us to estimate the column mass density. When plotted as a function of the distance from galaxies, it gives us mass distribution of galaxies as a function of the distance with the aid of N body simulations(dark matter only) which are constrained by the observed mass distribution. The result is that the mass associated with galaxies is extended to the middle to the neibouring galaxy, far beyond the virial radius, and the mass contained in the virial radius is only 25% of the total. This result applies both dark matter that is the main component of the galaxy and baryons. This also explains the discrepancy between the two mass density estimates, one using the luminosity density times the average mass-to-light ratio of galaxies and the other the global estimate using such as the cosmic microwave background fluctuation.The other conspicuous result is that dust is present not only in HI regions of galactic discs but also outside the galaxy, even beyond the virial radius, while dust is supposed to be produced by stars in galactic discs. The integrated amount of dust present outside galactic discs is as much as, or even more than, that in galactic discs. When added both component the amount of dust in the universe becomes consistent with the accumulated amount expected from the star formation history over the cosmic time. The extragalactic component accounts for missing dust in the cosmic energy inventory and it now closes.