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相关论文: A Test for the Origin of Quasar Redshifts

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In this letter, the old issue of whether redshifts of quasars are of cosmological origin is investigated. We make a plot of absorption redshifts versus emission redshifts for quasars with large amounts of data. Our study shows that, almost…

天体物理学 · 物理学 2007-05-23 Yi-Ping Qin , Guang-Zhong Xie , Xue-Tang Zheng , En-Wei Liang

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…

天体物理学 · 物理学 2009-11-11 E. Zackrisson

A crucial test of any cosmological model is the distribution of distant objects such as quasars. Because of well defined selection criteria quasars found by a ultraviolet excess (UVX) survey are ideal candidates for testing the model out to…

天体物理学 · 物理学 2009-10-22 David F. Crawford

A fundamental prediction of relativistic cosmologies is that, due to the expansion of space, observations of the distant cosmos should be time dilated and appear to run slower than events in the local universe. Whilst observations of…

宇宙学与河外天体物理 · 物理学 2023-06-08 Geraint F. Lewis , Brendon J. Brewer

Quasars of high redshift may be ejected from a nearby active galaxy of low redshift. This physical association then leads to the suggestion that the redshifts of quasars are not really an indication of their distances. In this…

综合物理 · 物理学 2007-05-23 Ching-Chuan Su

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…

综合物理 · 物理学 2016-09-07 Peter M. Hansen

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…

天体物理学 · 物理学 2009-09-25 Halton Arp

A sample of $60,410$ bona fide optical quasars with astrometric proper motions in Gaia EDR3 and spectroscopic redshifts above 0.5 in an oval 8400 square degree area of the sky is constructed. Using orthogonal Zernike functions of polar…

星系天体物理 · 物理学 2022-03-09 Valeri V. Makarov , Nathan J. Secrest

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…

综合物理 · 物理学 2013-10-02 Yi-Jia Zheng

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…

天体物理学 · 物理学 2008-11-26 M. B. Bell

We report hitherto unnoticed patterns in quasar light curves. We characterize segments of quasars' light curves with the slopes of the straight lines fit through them. These slopes appear to be directly related to the quasars' redshifts.…

宇宙学与河外天体物理 · 物理学 2015-06-04 De-Chang Dai , Glenn D. Starkman , Branislav Stojkovic , Dejan Stojkovic , Amanda Weltman

Gaia used a large sample of photometrically selected active galactic nuclei (AGNs) and quasars to remove the residual spin of its global proper motion system in order to achieve a maximally inertial reference frame. A small fraction of…

星系天体物理 · 物理学 2022-07-06 Valeri V. Makarov , Nathan J. Secrest

We present observations of 11 quasars, selected in the range z = 2.2-4.1, obtained with ESA's Superconducting Tunnel Junction (STJ) camera on the WHT. Using a single template quasar spectrum, we show that we can determine the redshifts of…

Advances in optical astrometry allow us to infer the non-radial kinematic structure of the Universe directly from observations. Here I use a supervised machine learning neural network method to predict 1.57 million redshifts based on…

星系天体物理 · 物理学 2025-07-03 Valeri V. Makarov

According to the Cosmological Principle an observer stationary with respect to the comoving coordinates of the expanding universe should find the redshift distribution of distant quasars to be isotropic. However, the observed redshift…

宇宙学与河外天体物理 · 物理学 2025-09-01 Ashok K. Singal

We examine the kinematics of the gas in the environments of galaxies hosting quasars at $z\sim2$. We employ 148 projected quasar pairs to study the circumgalactic gas of the foreground quasars in absorption. The sample selects foreground…

星系天体物理 · 物理学 2018-05-02 Marie Wingyee Lau , J. Xavier Prochaska , Joseph F. Hennawi

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…

宇宙学与河外天体物理 · 物理学 2014-10-02 J. Modzelewska , B. Czerny , M. Bilicki , K. Hryniewicz , M. Krupa , F. Petrogalli , W. Pych , A. Kurcz , A. Udalski

The evolution of optically selected quasars is usually supposed to be well described by a single constant parameter, either k_L or k_D, depending whether we refer to luminosity or density evolution. In this paper we present a study of the…

天体物理学 · 物理学 2007-05-23 Evanthia Hatziminaoglou , Ludovic Van Waerbeke , Guy Mathez

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,…

天体物理学 · 物理学 2007-05-23 Matthias Dietrich , Fred Hamann

A minority of the optically selected quasar population are red at optical wavelengths due to the presence of dust along the line-of-sight. A key focus of many red quasar studies is to understand their relationship with the overall quasar…

星系天体物理 · 物理学 2019-07-10 Lizelke Klindt , David M. Alexander , David J. Rosario , Elisabeta Lusso , Sotiria Fotopoulou
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