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Related papers: Time Dilation and Quasar Variability

200 papers

We report on the second installment of an X-ray monitoring project of seven luminous radio-quiet quasars (RQQs). New {\sl Chandra} observations of four of these, at $4.10\leq z\leq4.35$, yield a total of six X-ray epochs, per source, with…

High Energy Astrophysical Phenomena · Physics 2017-10-18 Ohad Shemmer , W. N. Brandt , Maurizio Paolillo , Shai Kaspi , Cristian Vignali , Paulina Lira , Donald P. Schneider

Quantum mechanics predicts deviations from exponential decay at short and long times, yet experimental evidence is limited. We report a power-law tail after $\sim$10 lifetimes in erythrosine~B fluorescence, confirmed by two detectors…

We investigate in detail an apparently unnoticed consequence of special relativity. It consists in time dilation/contraction and frequency shift for emitted light affecting accelerated reference frames at astronomical distances from an…

General Physics · Physics 2022-09-14 Germano D'Abramo

In our second paper on long-term quasar variability, we employ a much larger database of quasars than in de Vries, Becker & White. This expanded sample, containing 35165 quasars from the Sloan Digital Sky Survey Data Release 2, and 6413…

Astrophysics · Physics 2009-11-10 W. H. de Vries , R. H. Becker , R. L. White , C. Loomis

Time-like and space-like invariant space-time intervals are used to analyse measurements of spatial and temporal distances defined by two spatially-separated clocks. The time dilatation effect is confirmed, but not `relativity of…

General Physics · Physics 2009-09-01 J. H. Field

We first present the salient features of the gravitational time dilation and redshift effects in two ways; by considering the oscillation frequencies/rates of clocks at different heights/potentials and by considering the photons emitted by…

General Physics · Physics 2020-01-15 Murat Özer

I review the temporal/spectral data of accreting black hole sources paying most attention to the properties of the temporal variability such as photon energy dependent auto- and cross-correlation functions, average shot profiles and…

Astrophysics · Physics 2009-11-06 Juri Poutanen

Temporal fluctuations in the Hadamard walk on circles are studied. A temporal standard deviation of probability that a quantum random walker is positive at a given site is introduced to manifest striking differences between quantum and…

Quantum Physics · Physics 2007-05-23 Norio Inui , Yoshinao Konishi , Norio Konno , Takahiro Soshi

Possibility to detect DCC fluctuations is discussed. It is shown that interactions with quark background and dissipative effects due to interactions in the chiral field may result in damping of fluctuations. Since the magnitude of…

High Energy Physics - Phenomenology · Physics 2022-02-23 Zhonghan Feng , Denes Molnar , Laszlo Pal Csernai

A proper time observable for a quantum clock is introduced and it is found that the proper time read by one clock conditioned on another clock reading a different proper time obeys classical time dilation in accordance with special…

General Relativity and Quantum Cosmology · Physics 2023-01-04 Takeshi Chiba , Shunichiro Kinoshita

A fundamental property of an expanding universe is that any time dependent characteristic of distant objects must appear to scale by the factor $(1+z$). This is called time dilation. Light curves of type Ia supernovae and the duration of…

High Energy Astrophysical Phenomena · Physics 2019-03-06 David F. Crawford

Using the relativistic concept of time dilation we show that a superposition of gravitational potentials can lead to nonunitary time evolution. For sufficiently weak gravitational potentials one can still define, for all intents and…

We consider the effects of a shear on velocity fluctuations in a flow. The shear gives rise to a transient amplification that not only influences the amplitude of perturbations but also their time correlations. We show that, in the presence…

Chaotic Dynamics · Physics 2009-11-10 Bruno Eckhardt , Rahul Pandit

It has been suggested that the fuzzy nature of spacetime at the Planck scale may cause lightwaves to lose phase coherence, and if severe enough this could blur images of distant point-like sources sufficiently that they do not form an Airy…

Astrophysics · Physics 2008-11-26 Eric Steinbring

A relation between the variational slope, $s_F$ , and the mean absolute magnitude, $\langle M \rangle$, in the light curves of 58 spectroscopically confirmed quasars is measured with a dispersion of 0.15dex. Assuming it holds for quasars in…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-30 Rance Solomon , Dejan Stojkovic

We report preliminary results from a third sample of quasar absorption line spectra from the Keck telescope which has been studied to search for any possible variation of the fine structure constant, alpha. This third sample, which is…

Astrophysics · Physics 2009-08-18 J. K. Webb , M. T. Murphy , V. V. Flambaum , S. J. Curran

Detection of high-redshift absorption in the optical spectra of quasars have provided a powerful tool to measure spatial and temporal variations of physical ``constants'' in the Universe. It is demonstrated that high sensitivity to the…

Atomic Physics · Physics 2009-10-31 V. A. Dzuba , V. V. Flambaum , J. K. Webb.

We analytically and numerically investigate the evolutions of the scalar perturbations through the cycles with nonsingular bounce. It is found that the amplitude of the curvature perturbation on large scale will be amplified cycle by cycle,…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Zhi-Guo Liu , Yun-Song Piao

We investigate the effect of the redshift drift in strong gravitational lensing. The redshift drift produces a time variation of $i)$ the apparent position of a lensed source and $ii)$ the time delay among incoming signals from different…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-17 Oliver F. Piattella , Leonardo Giani

Broad absorption lines (BALs) in quasar spectra identify high velocity outflows that likely exist in all quasars and could play a major role in feedback to galaxy evolution. The variability of BALs can help us understand the structure,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Daniel M. Capellupo , Fred Hamann , Joseph C. Shields , Paola Rodríguez Hidalgo , Tom A. Barlow