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The theory of mesoscopic fluctuations is applied to inhomogeneous solids consisting of chaotically distributed regions with different crystalline structure. This approach makes it possible to describe statistical properties of such mixture…

Statistical Mechanics · Physics 2015-06-25 V. I. Yukalov

Cosmic shear measurements rely on our ability to measure and correct the Point Spread Function (PSF) of the observations. This PSF is measured using stars in the field, which give a noisy measure at random points in the field. Using Wiener…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 A. Amara , A. Refregier , S. Paulin-Henriksson

A standard approach to study time-dependent stochastic processes is the power spectral density (PSD), an ensemble-averaged property defined as the Fourier transform of the autocorrelation function of the process in the asymptotic limit of…

Statistical Mechanics · Physics 2019-09-04 Vittoria Sposini , Ralf Metzler , Gleb Oshanin

The cataclysmic variable MV Lyr was present in the Kepler field yielding a light curve with the duration of almost 1500 days with 60 second cadence. Such high quality data of this nova-like system with obvious fast optical variability show…

Solar and Stellar Astrophysics · Physics 2020-01-08 A. Dobrotka , H. Negoro , S. Mineshige

Understanding the rate at which stars form is central to studies of galaxy formation. Observationally, the star formation rates (SFRs) of galaxies are measured using the luminosity in different frequency bands, often under the assumption of…

Microfading Spectrometry (MFS) is a method for assessing light sensitivity color (spectral) variations of cultural heritage objects. Each measured point on the surface gives rise to a time-series of stochastic observations that represents…

We use optical data from the Palomar Transient Factory (PTF) and the Catalina Real-Time Transient Survey (CRTS) to study the variability of gamma-ray detected and non-detected objects in a large population of active galactic nuclei (AGN)…

Scientific fields such as insider-threat detection and highway-safety planning often lack sufficient amounts of time-series data to estimate statistical models for the purpose of scientific discovery. Moreover, the available limited data…

Machine Learning · Statistics 2018-03-16 Daniel Emaasit , Matthew Johnson

When a coherent laser beam impinges on a random sample (e.g. a colloidal suspension), the scattered light exhibits characteristic speckles. If the temporal coherence of the light source is too short, then the speckles disappear, along with…

Optics · Physics 2011-12-13 D. Brogioli , D. Salerno , F. Croccolo , R. Ziano , F. Mantegazza

This paper develops a framework for fitting functions with domains in the Euclidean space, when data are sparse but a slow variation allows for a useful fit. We measure the variation by Lipschitz Bound (LB). Functions which admit smaller LB…

Methodology · Statistics 2014-07-07 Reza Hosseini , Akimichi Takemura , Kiros Berhane

Using large scale numerical simulations we analyze the statistical properties of fracture in the two dimensional random spring model and compare it with its scalar counterpart: the random fuse model. We first consider the process of crack…

Materials Science · Physics 2009-11-11 Phani Kumar V. V. Nukala , Stefano Zapperi , Srdan Simunovic

Context. We present the light curves of six BL Lac objects, PKS 0537-441, PKS 0735+17, OJ 287, PKS 2005-489, PKS 2155-304, W Comae, and of the flat spectrum radio quasar PKS 1510-089, as a part of a photometric monitoring program in the…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Angela Sandrinelli , Stefano Covino , Aldo Treves

The amplitude of density turbulence in the extended solar corona, especially near the dissipation scale, impinges on several problems of current interest. Radio sources observed through the turbulent solar wind are broadened due to…

Solar and Stellar Astrophysics · Physics 2015-06-23 M. Ingale , P. Subramanian , Iver Cairns

To investigate universal behavior and effects of long-range temporal correlations in kinetic roughening, we perform extensive simulations on the Kardar-Parisi-Zhang (KPZ) equation with temporally correlated noise based on pseudospectral…

Statistical Mechanics · Physics 2023-04-18 Xiongpeng Hu , Dapeng Hao , Hui Xia

Spectral densities encode non-perturbative information that enters the calculation of a plethora of physical observables in strongly coupled field theories. Phenomenological applications encompass aspects of standard-model hadronic physics,…

The blazar sequence, including negative correlations between radiative luminosity $L_{\rm rad}$ and synchrotron peak frequency $\nu$, and between Compton dominance $Y$ and $\nu$, is widely adopted as a phenomenological description of…

High Energy Astrophysical Phenomena · Physics 2024-02-16 Zhu-Jian Wan , Rui Xue , Ze-Rui Wang , Hu-Bing Xiao , Jun-Hui Fan

Despite their ability to represent highly expressive functions, deep learning models seem to find simple solutions that generalize surprisingly well. Spectral bias -- the tendency of neural networks to prioritize learning low frequency…

Machine Learning · Computer Science 2022-09-30 Sara Fridovich-Keil , Raphael Gontijo-Lopes , Rebecca Roelofs

Auto- and cross-spectral density functions for dynamic {random} fields and power are derived. These are based on first- and second-order Pad\'{e} approximants of correlation functions expanded in terms of spectral moments. The second-order…

Classical Physics · Physics 2024-04-04 Luk R. Arnaut

Because many of our X-ray telescopes are optimized towards observing faint sources, observations of bright sources like X-ray binaries in outburst are often affected by instrumental biases. These effects include dead time and photon…

Instrumentation and Methods for Astrophysics · Physics 2021-12-22 D. Huppenkothen , M. Bachetti

Robust state estimation in coupled dynamical systems depends critically not only on sensor quality but on the structural alignment between observation channels and the system's intrinsic dynamics. This paper develops a rigorous framework…

Systems and Control · Electrical Eng. & Systems 2026-05-08 Somasundhar Venkatasubramanian , Anirudh Venkat , Advaidh Venkat