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We introduce and apply a methodology based on dynamic time warping (DTW) to compare the whole set of gamma-ray light curves reported in the Third Fermi-Large Area Telescope Pulsar Catalogue. Our method allows us to quantitatively measure…

High Energy Astrophysical Phenomena · Physics 2025-03-05 C. R. García , Diego F. Torres

Periodic light curve behavior predicted for some binary black hole systems might be detected in large samples, such as the multi-million quasar sample expected from the Large Synoptic Survey Telescope (LSST). We investigate the false-alarm…

Instrumentation and Methods for Astrophysics · Physics 2010-12-20 David B. Westman , Chelsea L. MacLeod , Zeljko Ivezic

Accurate methods for reverberation mapping using photometry are highly sought after since they are inherently less resource intensive than spectroscopic techniques. However, the effectiveness of photometric reverberation mapping for…

Astrophysics of Galaxies · Physics 2020-01-08 S. C. Read , D. J. B. Smith , M. J. Jarvis , G. Gurkan

In this paper, we consider a spectral analysis of the Correlated Random Walk (CRW) on the path. We apply an analytical method for the Quantum Walk to CRW. For the isospectral coin cases, we obtain all of the eigenvalues and the…

Probability · Mathematics 2023-11-01 Yusuke Ide , Akihiro Narimatsu

A correlated Gaussian random walk(CGRW) model is proposed as a simple model of animal dispersal. The general features of CGRW is described. We will discuss how from this single model a number of different kinds of correlated random walk can…

Statistical Mechanics · Physics 2012-01-10 Trilochan Bagarti

We use both simulated and real quasar light curves to explore modeling photometric reverberation-mapping (RM) data as a stochastic process. We do this using modifications to our previously developed RM method based on modeling quasar…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-30 Ying Zu , C. S. Kochanek , Szymon Kozłowski , B. M. Peterson

Rules for quantizing the walker+coin parts of a classical random walk are provided by treating them as interacting quantum systems. A quantum optical random walk (QORW), is introduced by means of a new rule that treats quantum or classical…

Quantum Physics · Physics 2009-11-13 Demosthenes Ellinas , Ioannis Smyrnakis

The variability of active galactic nuclei (AGNs) is ubiquitous but has not yet been understood. Measuring the optical variation properties of AGNs, such as variation timescale and amplitude, and then correlating them with their fundamental…

Astrophysics of Galaxies · Physics 2024-01-11 Xu-Fan Hu , Zhen-Yi Cai , Jun-Xian Wang

We investigate a novel quantum random walk (QRW) model, possibly useful in quantum algorithm implementation, that achieves a quadratically faster diffusion rate compared to its classical counterpart. We evaluate its asymptotic behavior…

Quantum Physics · Physics 2016-09-08 Demosthenes Ellinas , Ioannis Smyrnakis

We compare quasar selection techniques based on their optical variability using data from the Catalina Real-time Transient Survey (CRTS). We introduce a new technique based on Slepian wavelet variance (SWV) that shows comparable or better…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-05 Matthew J. Graham , S. G. Djorgovski , Andrew J. Drake , Ashish A. Mahabal , Melissa Chang , Daniel Stern , Ciro Donalek , Eilat Glikman

Continuous time random walks (CTRWs) are used in physics to model anomalous diffusion, by incorporating a random waiting time between particle jumps. In finance, the particle jumps are log-returns and the waiting times measure delay between…

Data Analysis, Statistics and Probability · Physics 2008-12-10 Mark M. Meerschaert , Enrico Scalas

Quantum walk (QW), which is considered as the quantum counterpart of the classical random walk (CRW), is actually the quantum extension of CRW from the single-coin interpretation. The sequential unitary evolution engenders correlation…

Quantum Physics · Physics 2020-03-11 Jin-Fu Chen , Yu-Han Ma , Chang-Pu Sun

It has been alleged in several papers that the so called delayed continuous-time random walks (DCTRWs) provide a model for the one-dimensional telegraph equation at microscopic level. This conclusion, being widespread now, is strange, since…

Statistical Mechanics · Physics 2012-03-01 Sergey A. Rukolaine , Alexander M. Samsonov

We use numerical simulations to test a broad range of plausible observational strategies designed to measure the time delay between the images of gravitationally lensed quasars. Artificial quasar light curves are created along with…

Astrophysics · Physics 2009-11-10 A. Eigenbrod , F. Courbin , C. Vuissoz , G. Meylan , P. Saha , S. Dye

The foundations of the fractional diffusion equation are investigated based on coupled and decoupled continuous time random walks (CTRW). For this aim we find an exact solution of the decoupled CTRW, in terms of an infinite sum of stable…

Statistical Mechanics · Physics 2009-11-07 Eli Barkai

Algebraic random walks (ARW) and quantum mechanical random walks (QRW) are investigated and related. Based on minimal data provided by the underlying bialgebras of functions defined on e. g the real line R, the abelian finite group Z_N, and…

Quantum Physics · Physics 2007-05-23 Demosthenes Ellinas

We study the optical light curves - primarily probing the variable emission from the accretion disk - of ~ 900 extreme variability quasars (EVQs, with maximum flux variations more than 1 mag) over an observed-frame baseline of ~ 16 years…

Astrophysics of Galaxies · Physics 2020-04-14 Yuanze Luo , Yue Shen , Qian Yang

We introduce a discrete-time quantum random walk (QRW) framework for spatial epidemic modelling on a two-dimensional square lattice and compare its dynamics to classical random-walk SIR models. In our model, each infected site spawns a…

Quantum Physics · Physics 2025-09-15 Sayan Manna , Nikhil Kowshik , Sudebkumar Prasant Pal

When a flux-limited quasar sample is observed at later times, there will be more dimmed quasars than brightened ones, due to a selection bias induced at the time of sample selection. Quasars are continuously varying and there are more…

Astrophysics of Galaxies · Physics 2021-09-08 Yue Shen , Colin J. Burke

In a continuous time random walk (CTRW), each random jump follows a random waiting time. CTRW scaling limits are time-changed processes that model anomalous diffusion. The outer process describes particle jumps, and the non-Markovian inner…

Probability · Mathematics 2016-11-29 Mark M. Meerschaert , Erkan Nane , Yimin Xiao