We use numerical and analytic approaches to calculate the growth of density fluctuations induced by global texture in an Ω = 1 cold dark matter (CDM) cosmogony. The resulting power spectra are in good agreement with each other, with more power on large scales than in the standard inflation plus CDM model. We calculate various related statistics, including two-point correlation functions, mass variances, and the cosmic Mach number - our results indicate that the texture plus CDM cosmogony compares more favorably than standard CDM with the observations of large-scale structure. Texture produces coherent velocity fields on large scales, in agreement with observation, although the small-scale velocity dispersions appear excessive. Also, while structure on scales corresponding to the observed "bubbles" is produced, the voids appear less empty than observed if one assumes light traces mass. Both of these problems may he cured when baryonic physics is included. The topology of the cosmic structure found in the simulations agrees well with that observed. The non-Gaussian texture induced density fluctuations lead to earlier nonlinear object formation than in Gaussian models and may also be more compatible with recent evidence that the galaxy density Held is non-Gaussian on large scales. On smaller scales, the density field is strongly non-Gaussian, but this appears to be primarily due to nonlinear gravitational clustering. The velocity field on smaller scales is surprisingly Gaussian.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science
- Cosmic microwave background
- Dark matter
- Large-scale structure of universe