Related papers: Quasars and the Hubble Relation
The distribution on the sky of clusters of galaxies shows significant association with relatively nearby, large, active galaxies. The pattern is that of clusters paired equidistant across a central galaxy with the apparent magnitudes and…
Analysis of ROSAT observations demonstrate that X-ray sources are associated with bright Seyfert galaxies up to distances of about 40 arc min. These X-ray sources are predominantly identified with blue stellar objects (BSO's) some of which…
Quasars have reigned as the most luminous and distant objects in the Universe. These concepts were based on the hypothesis that the redshifts of quasars are obeying the Hubble low. This hypothesis has little serious competition today, but…
According to the Hubble law, high redshift objects such as Quasar (QSOs), X-ray Active Galactic Nuclei (AGN) together with the Gamma Ray Burst (GRBs) are the fastest and farthest objects. These characteristics provides strong motivations…
I review recent observations on the evolution of quasars, describe new surveys for quasars at z > 5 and for quasars at z > 3.3 down to luminosities corresponding to L* galaxies, and note the possible connection between the evolution of the…
If high-redshift QSOs are ejected from the nuclei of low-redshift galaxies, as some have claimed, a large portion of their redshift must be intrinsic (non-Doppler). If these intrinsic components have preferred values, redshifts will tend to…
Star-forming galaxies at high redshift show anomalous values of infrared excess, which can be described only by extremizing the existing relations between the shape of their ultraviolet continuum emission and their infrared-to-ultraviolet…
I review recent results for quasars and discuss how they are related to activity in galaxies. Topics included are studies of quasar host galaxies with HST; searches for quasars in the Hubble Deep Field; evolution of the quasar luminosity…
Despite a general consensus in the astronomical community that all quasars are located at the distances implied by their redshifts, a number of observations still challenge this interpretation, possibly indicating that some subpopulation of…
Quasars are among the most luminous objects in the universe, and they can be studied in detail up to the highest known redshift. Assuming that the gas associated with quasars is closely related to the interstellar medium of the host galaxy,…
Proceeding of the "HACK100" Conference, 6-10 June 2022, Trieste, Italy - In recent years, quasars have been shown to be reliable standardizable candles, thanks to the non-linear relation between their X-rays and ultraviolet luminosity.…
Growing amount of data show evidence for statistical and apparent physical association between low-redshift galaxies and high-redshift quasi-stellar objects, suggesting noncosmological origin of their redshift and failure of classical…
Observations increasingly demonstrate the spatial association of high redshift objects with larger, low redshift galaxies. These companion objects show a continuous range of physical properties - from very compact, high redshift quasars,…
We have investigated the spatial distribution of quasars and its relationship with redshift by using the two-point correlation function, the variance of cell counts and the conditional density as a function of redshift. By comparing our…
Analysis of the deepest available images of the sky, obtained by the Hubble Space Telescope, reveals a large number of candidate high-redshift galaxies. A catalogue of 1,683 objects is presented, with estimated redshifts ranging from $z=0$…
An "exotic" idea proposed by Viktor Ambartsumian was that new galaxies are formed through the ejection from older active galaxies. Galaxies beget galaxies, instead of the standard scenario in which galaxies stem from the evolution of the…
Quasars (QSOs) are extremely luminous active galatic nuclei currently observed up to redshift $z=7.642$. As such, they have the potential to be the next rung of the cosmic distance ladder beyond SNe Ia, if they can reliably be used as…
As recently suggested, nearby quasar remnants are plausible sites of black-hole based compact dynamos that could be capable of accelerating ultra-high energy cosmic rays (UHECRs). In such a model, UHECRs would originate at the nuclei of…
There is a growing consensus that the emergence of quasars at high redshifts is related to the onset of galaxy formation, suggesting that the detection of concentrations of gas accompanying such quasars should provide clues about the early…
Quasars, as the most luminous persistent sources in the Universe, have broad applications for cosmological studies. In particular, they can be employed to directly measure the expansion history of the Universe, similarly to SNe Ia. The…