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Related papers: Analysis of quasar magnitudes

200 papers

An anomaly in the distribution of quasar magnitudes based on the SDSS survey, has been recently reported by Longo (2012). The angular size of this anomaly is of the order of $\rm \pm 15^o$ on the sky. A low surface brightness smooth…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Edmond Giraud

QSOs and radio-galaxies, together with the CMB, ``normal'' galaxies and clusters, represent the main source of information about the origin and evolution of the Large Scale Structure. They can be used either directly, as tracers of the…

Astrophysics · Physics 2007-05-23 S. Cristiani

The common attribute of all Big Bang cosmologies is that they are based on the assumption that the universe is expanding. However examination of the evidence for this expansion clearly favours a static universe. The major topics considered…

General Physics · Physics 2014-07-10 David F. Crawford

Observations conducted over the last few decades show that the expansion of the Universe is accelerating. In the standard model of cosmology, this accelerated expansion is attributed to a dark energy in the form of a cosmological constant.…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-22 Joseph Ryan

Once understood as the paradigm of passively evolving objects, the discovery that massive galaxies experienced an enormous structural evolution in the last ten billion years has opened an active line of research. The most significant…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Ignacio Trujillo

The large observed redshift of quasars has suggested large cosmological distances and a corresponding enormous energy output to explain the brightness or luminosity as seen at earth. Alternative or complementary sources of redshift have not…

General Physics · Physics 2016-09-07 Peter M. Hansen

The observational evidence for the existence of a non-zero cosmological constant is getting stronger. It is therefore timely to address the question of its eventual effect on the dynamics of galaxies, clusters and larger structures in the…

Astrophysics · Physics 2007-05-23 L. Bergstrom , U. Danielsson

Detecting any evolution of dimensionless in the ratios of physical quantities, such as the fine structure constant, would prove that the Weak Equivalence Principle is violated and lead to a paradigm shift in physics. High resolution…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-03 Dinko Milaković

The distribution of SDSS quasars is described. The dependence of observational number of quasars within distances to an observer less than r on distance r is found to be the power law with correlation dimension value equal 2,71 in redshift…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 I. K. Rozgacheva , A. A. Agapov

The standard model of cosmology is based on the general theory of relativity and demands more than 95\% of the universe to consist of dark matter and dark energy that has no direct observational evidence till date. The foundation of the…

General Relativity and Quantum Cosmology · Physics 2015-04-13 Santanu Das

The traditional "explanation" for the observed acceleration of the universe is the existence of a positive cosmological constant. However, this can hardly be a truly convincing explanation, as an expanding universe is not expected to have a…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Joan Sola

We analyze Hubble Space Telescope observations of scattering regions in 20 luminous obscured quasars at $0.24<z<0.65$ (11 new observations and 9 archival ones) observed at rest-frame $\sim 3000$\AA. We find spectacular $5-10$ kpc-scale…

Astrophysics of Galaxies · Physics 2016-01-27 Georges Obied , Nadia L. Zakamska , Dominika Wylezalek , Guilin Liu

We investigate the luminosity dependence of quasar clustering, inspired by numerical simulations of galaxy mergers that incorporate black hole growth. These simulations have motivated a new interpretation of the quasar luminosity function.…

Astrophysics · Physics 2009-11-13 Adam Lidz , Philip F. Hopkins , Thomas J. Cox , Lars Hernquist , Brant Robertson

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…

Astrophysics · Physics 2007-05-23 P. Andreani , S. Cristiani , F. La Franca

We pay particular attention to the high end of the $\lya$ optical depth distribution of a quasar spectrum. Based on the flux distribution (Miralda-Escud\'e et al 1996), a simple yet seemingly cosmological model -differentiating statistic,…

Astrophysics · Physics 2016-08-30 Renyue Cen

It is necessary to make assumptions in order to derive models to be used for cosmological predictions and comparison with observational data. In particular, in standard cosmology the spatial curvature is assumed to be constant and zero (or…

General Relativity and Quantum Cosmology · Physics 2019-05-14 A. A. Coley

The evolution of quasar clustering is investigated with a new sample of 388 quasars with 0.3<z<=2.2, B<=20.5 and Mb<-23, selected over an area of 24.6 sq. deg. in the South Galactic Pole. Assuming a two-point correlation function of the…

Astrophysics · Physics 2009-10-30 Fabio La Franca , Paola Andreani , Stefano Cristiani

We show that the evolution of the quintessence energy density $\Omega_Q$ is model independent in an accelerating universe. The accelerating behaviour has lasted at most 0.5 e-folds of expansion assuming a present day value of…

Astrophysics · Physics 2008-11-26 A. de la Macorra

We present limits on the cosmological constant from the statistics of gravitational lenses using newly completed quasar surveys, new lens data, and a range of lens models. The formal limit is $\lambda_0 < 0.66$ at 95\% confidence in flat…

Astrophysics · Physics 2009-10-28 C. S. Kochanek

Apparent magnitudes are important for high precision cosmology. It is generally accepted that weak gravitational lensing does not affect the relationship between apparent magnitude and redshift. By considering metric perturbations it is…

Astrophysics · Physics 2009-11-06 Hamish G. Rose