Rhombic cell analysis as outlined in the first paper of the present series is applied to samples of varying depths and liming luminosities of the IRAS/PSCz Catalogue. Numerical indices are introduced to summarize esse...Rhombic cell analysis as outlined in the first paper of the present series is applied to samples of varying depths and liming luminosities of the IRAS/PSCz Catalogue. Numerical indices are introduced to summarize essential information. Because of the discrete nature of the analysis and of the space distribution of galaxies, the indices for a given sample must be regarded as each having an irreducible scatter. Despite the scatter, the mean indices show remarkable variations across the samples. The underlying factor for the variations is shown to be the limiting luminosity rather than the sampling depth. As samples of more and more luminous galaxies are considered over a range of some 2.5 magnitudes (a factor of some 75 in space density), the morphology of the filled and empty regions defined by the galaxies degrades steadily towards insignificance, and the degrading is faster for the filled than the empty region.展开更多
A new way of probing the large-scale structure of the universe is proposed. Space is partitioned into cells the shape of rhombic dodecahedron. The cells are labelled 'filled' or 'empty' according as th...A new way of probing the large-scale structure of the universe is proposed. Space is partitioned into cells the shape of rhombic dodecahedron. The cells are labelled 'filled' or 'empty' according as they contain galaxies or not. The cell size is so chosen as to have nearly equal numbers of filled and empty cells for the given galaxy sample. Two observables on each cell are definable: the number of its like neighbors, n1, and a two-suffixed topological type τ, the suffixes being the numbers of its like and unlike neighbor-groups. The frequency distributions of n1 and T in the observed set of filled (empty) cells are then considered as indicators of the morphology of the set. The method is applied to the CfA catalogue of galaxies as an illustration. Despite its limited size, the data offers evidence 1) that the empty cells are more strongly clustered than the filled cells, and 2) that the filled cells, but not the empty cells, have a tendency to occur in sheets. Further directions of development both in theory and application are indicated.展开更多
文摘Rhombic cell analysis as outlined in the first paper of the present series is applied to samples of varying depths and liming luminosities of the IRAS/PSCz Catalogue. Numerical indices are introduced to summarize essential information. Because of the discrete nature of the analysis and of the space distribution of galaxies, the indices for a given sample must be regarded as each having an irreducible scatter. Despite the scatter, the mean indices show remarkable variations across the samples. The underlying factor for the variations is shown to be the limiting luminosity rather than the sampling depth. As samples of more and more luminous galaxies are considered over a range of some 2.5 magnitudes (a factor of some 75 in space density), the morphology of the filled and empty regions defined by the galaxies degrades steadily towards insignificance, and the degrading is faster for the filled than the empty region.
文摘A new way of probing the large-scale structure of the universe is proposed. Space is partitioned into cells the shape of rhombic dodecahedron. The cells are labelled 'filled' or 'empty' according as they contain galaxies or not. The cell size is so chosen as to have nearly equal numbers of filled and empty cells for the given galaxy sample. Two observables on each cell are definable: the number of its like neighbors, n1, and a two-suffixed topological type τ, the suffixes being the numbers of its like and unlike neighbor-groups. The frequency distributions of n1 and T in the observed set of filled (empty) cells are then considered as indicators of the morphology of the set. The method is applied to the CfA catalogue of galaxies as an illustration. Despite its limited size, the data offers evidence 1) that the empty cells are more strongly clustered than the filled cells, and 2) that the filled cells, but not the empty cells, have a tendency to occur in sheets. Further directions of development both in theory and application are indicated.
