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11.
On the basis of the solutions obtained in the previous paper, the changes in the scenario of the standard model of the Big Bang are found. The chaos degree (constrainst on fluctuation spectra) is obtained, which could be still preserved by the initially completely chaotic Universe at the time of light elements nucleosynthesist
es. The time boundaries of hadron and lepton eras and the time the electron neutrinos and neutrons become frozen in reactions of weak interaction may be shifted up to 1.4 times. The corresponding temperatures may shift off from the standard ones 0.88 times if the mean-square level of fluctuations is close to unity. If the density of the energy of fluctuations concentrated in the short-wave region of the spectrum is less than 1.5
–
, the nucleosynthesis leads to a helium abundance coinciding with the observe one. If at the timet
es the maximum of the spectral density of the energy is in the long-wave region, that is max ct
es
the level of the chaos during the period of nucleosynthesis is restricted to 1.76 (where |C
K
|2 d3
K,C
K
is Fourier component of the amplitude of metric fluctuations). In particular, the protogalactic vortical disturbances with a wide spectrum 4 × 103 -1( = K/K, = /crit) are compatible with the observed helium abundance. 相似文献
12.
V. Müller S. Arbabi-Bidgoli J. Einasto D. Tucker 《Monthly notices of the Royal Astronomical Society》2000,318(1):280-288
We analysed the distribution of void sizes in the two-dimensional slices of the Las Campanas Redshift Survey (LCRS). Fourteen volume-limited subsamples were extracted from the six slices to cover a large part of the survey and to test the robustness of the results against cosmic variance. Thirteen samples were randomly culled to produce homogeneously selected samples. We then studied the relationship between the cumulative area covered by voids and the void size as a property of the void hierarchy. We found that the distribution of void sizes scaled with the mean galaxy separation, λ . In particular, we found that the size of voids covering half of the area is given by D med ≈ λ +(12±3) h −1 Mpc. Next, by employing an environmental density threshold criterion to identify mock galaxies, we were able to extend this analysis to mock samples from dynamical N -body simulations of cold dark matter (CDM) models. To reproduce the observed void statistics, overdensity thresholds of δ th ≈0,…,1 are necessary. We compared standard (SCDM), open (OCDM), vacuum energy dominated (ΛCDM) and broken scale invariant CDM models (BCDM): we found that both the void size distribution and the two-point correlation function provided important and complementary information on the large-scale matter distribution. The dependence of the void statistics on the threshold criterion for the mock galaxy identification showed that the galaxy biasing was more crucial for the void size distribution than were differences between the cosmological models. 相似文献
13.
D. Calzetti J. Einasto M. Giavalisco R. Ruffini E. Saar 《Astrophysics and Space Science》1987,137(1):101-106
The observational data on the amplitude of the correlation function of galaxies in the direction of the Coma cluster are confronted with an analytic formula derived for a self-similar observer-homogeneous structure. 相似文献