Related papers: Apparent discordant redshift QSO-galaxy associatio…
Galaxies undergoing formation and evolution can now be observed over a time baseline of some 12 Gyr. An inherent difficulty with high-redshift observations is that the objects are very faint and the best resolution (HST) is only ~0.5 kpc.…
I discuss recent theoretical work on the formation and evolution of galaxies paying particular attention to the ability of current models to make detailed comparisons with observations of the galaxy population both nearby and at high…
The effects of late gas accretion episodes and subsequent merger-induced starbursts on the photo-chemical evolution of elliptical galaxies are studied and compared to the picture of galaxy formation occurring at high redshift with an unique…
Galaxies form out of small fluctuations in a smoothly expanding Universe. However, the initial gravitational collapse phase is accompanied by the formation of supermassive black holes and clusters of massive stars. Black holes and star…
We present an alternative interpretation of the observations of BR1202-0725 at z=4.695 and show that its properties are consistent with a relativistic jet, issuing from the quasar core, propagating into the inter-galactic medium and…
Hydrodynamic cosmological simulations predict that the average opacity of the Ly-alpha forest should increase in the neighborhood of galaxies because galaxies form in dense environments. Recent observations (Adelberger et al. 2002) confirm…
The existence of massive ($10^{11}$ solar masses) elliptical galaxies by redshift z~4 (when the Universe was 1.5 billion years old) necessitates the presence of galaxies with star-formation rates exceeding 100 solar masses per year at z>6…
The standard cosmological model, now strongly constrained by direct observation at early epochs, is very successful in describing the structure of the evolved universe on large and intermediate scales. Unfortunately, serious contradictions…
We investigate the evolution of clusters of galaxies in a sample of distant clusters with redshifts between 0.3 and 1.0. We show the abilities and limitations of combined ROSAT and ASCA data to draw cosmological conclusions. For the first…
Massive, quiescent galaxies at high redshift have been found to be considerably more compact than galaxies of similar mass in the local universe. How these compact galaxies formed has yet to be determined, though several progenitor…
Galaxies are complex systems the evolution of which apparently results from the interplay of dynamics, star formation, chemical enrichment, and feedback from supernova explosions and supermassive black holes. The hierarchical theory of…
Astronomers traditionally find steep, open-ended functions difficult: the log N - log S curve for example, or the probability-area-radius relation in making cross-waveband identifications. The debate over the existence of a redshift cutoff…
We consider the proposition that multiple universes exist by reviewing the various manifestations. In recent years, this idea has been elevated from science fiction and introduced in separate guises as an explanation for coincidence…
We have studied the distribution of $B_J<20.5$ galaxies from the ROE/NRL COSMOS/UKST catalogue around two samples of $z>0.3$ QSOs with similar redshift distributions. The first sample is formed by 144 radio-loud QSOs from the Parkes…
The latest observations of molecular gas and the atomic hydrogen content of local and high-redshift galaxies, coupled with how these correlate with star formation activity, have revolutionized our ideas about how to model star formation in…
High-redshift (z > 2) massive quiescent (MQ) galaxies provide an opportunity to probe the key physical processes driving the fuelling and quenching of star formation in the early Universe. Observational evidence suggests a possible…
Older and more recent pieces of observational evidence suggest a strong connection between QSOs and galaxies; in particular, the recently discovered correlation between black hole and galactic bulge masses suggests that QSO activity is…
The first and most compelling evidence of the universe's expansion was, and continues to be, the observed redshift of spectra from distant objects. This paper plays "devil's advocate" by providing an alternative explanation with elementary…
We present a sample of $i_{775}$-dropout candidates identified in five Hubble Advanced Camera for Surveys fields centered on Sloan Digital Sky Survey QSOs at redshift $z\sim 6$. Our fields are as deep as the Great Observatory Origins Deep…
With the advent of the next generation wide-field cameras it became possible to survey in an unbiased mode galaxies spanning a variety of local densities, from the core of rich clusters, to compact and loose groups, down to filaments and…