English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

A recent observation of Steidel et al. indicates that a substantial fractionof giant galaxies were formed at an epoch as early as redshift $z>3-3.5$. Weshow that this early formation of giant galaxies gives strong constraints onmodels of cosmic structure formation. Adopting the COBE normalization for thedensity perturbation spectrum, we argue that the following models do not havelarge enough power on galactic scales to yield the observed abundance: (i)standard cold dark matter (CDM) models (where mass density $\Omega_0=1$ andpower index $n=1$) with the Hubble constant $h\lsim 0.35$; (ii) tilted CDMmodels with $h=0.5$ and $n\lsim 0.75$; (iii) open CDM models with $h\lsim 0.8$and $\Omega_0 \lsim 0.3$, and (iv) mixed dark matter models with $h=0.5$ and$\Omega _\nu \gsim 0.2$. Flat CDM models with a cosmological constant$\lambda_0 \sim 0.7$ are consistent with the observation, provided that $h\gsim0.6$. Combined with constraints from large-scale structure formation, theseresults imply that the flat CDM model with a low $\Omega_0$ is the only onethat is fully consistent with observations. We predict that these high-redshiftgalaxies are more strongly clustered than normal galaxies observed today.Comment: 14 pages, Latex(aaspp4.sty), 3 encap. ps fig

Constraints on the Cosmic Structure Formation Models from Early Formation of Giant Galaxies