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We present an approximate form for the weak lensing magnification distribution of standard candles, valid for all cosmological models, with arbitrary matter distributions, over all redshifts. Our results are based on a universal probability…

Astrophysics · Physics 2009-11-07 Yun Wang , Daniel E. Holz , Dipak Munshi

The classical stochastic model of cosmology recently developed by us is reconsidered. In that approach the parameter $w$ defined by the equation of state $p=w{\rho}$ was taken to be fluctuating with mean zero and we compared the theoretical…

Astrophysics · Physics 2009-11-07 Moncy V. John , C. Sivakumar , K. Babu Joseph

The probability distribution function of column density (PDF) has become the tool of choice for cloud structure analysis and star formation studies. Its simplicity is attractive, and the PDF could offer access to cloud physical parameters…

Astrophysics of Galaxies · Physics 2017-10-11 João Alves , Marco Lombardi , Charles Lada

Many astrophysical analyses depend on estimates of redshifts (a proxy for distance) determined from photometric (i.e., imaging) data alone. Inaccurate estimates of photometric redshift uncertainties can result in large systematic errors.…

Instrumentation and Methods for Astrophysics · Physics 2022-05-31 Biprateep Dey , Jeffrey A. Newman , Brett H. Andrews , Rafael Izbicki , Ann B. Lee , David Zhao , Markus Michael Rau , Alex I. Malz

If two probability density functions (PDFs) have values for their first $n$ moments which are quite close to each other (upper bounds of their differences are known), can it be expected that the PDFs themselves are very similar? Shown below…

Statistics Theory · Mathematics 2018-08-16 Pranava Chaitanya Jayanti , Konstantina Trivisa

The formula for probability density functions (PDFs) has been extended to include PDF for energy dissipation rates in addition to other PDFs such as for velocity fluctuations, velocity derivatives, fluid particle accelerations, energy…

Statistical Mechanics · Physics 2009-11-11 T. Arimitsu , N. Arimitsu

We study the non-Gaussian tail of the probability distribution function of density in cosmological N-Body simulations for a variety of initial conditions. We compare the behaviour of the non-Gaussian tail in the real space with that in the…

Astrophysics · Physics 2007-05-23 J. S. Bagla , Suryadeep Ray

We derive a multifractal model for the velocity probability density distribution function (PDF), which is valid from the inertial range to the viscous range. The model gives a continuous evolution of velocity PDFs from large to small…

chao-dyn · Physics 2008-02-03 Jens Eggers , Z. Jane Wang

Probability distribution functions (PDFs) of column densities are an established tool to characterize the evolutionary state of interstellar clouds. Using simulations, we show to what degree their determination is affected by noise,…

Instrumentation and Methods for Astrophysics · Physics 2016-05-25 Volker Ossenkopf-Okada , Timea Csengeri , Nicola Schneider , Christoph Federrath , Ralf S. Klessen

The probability density function (PDF) of velocity fluctuations is studied experimentally for grid turbulence in a systematical manner. At small distances from the grid, where the turbulence is still developing, the PDF is sub-Gaussian. At…

Fluid Dynamics · Physics 2009-11-07 H. Mouri , M. Takaoka , A. Hori , Y. Kawashima

While the problem of estimating a probability density function (pdf) from its observations is classical, the estimation under additional shape constraints is both important and challenging. We introduce an efficient, geometric approach for…

Methodology · Statistics 2018-04-05 Sutanoy Dasgupta , Debdeep Pati , Ian H. Jermyn , Anuj Srivastava

The probability density function (PDF) of a random variable associated with the solution of a partial differential equation (PDE) with random parameters is approximated using a truncated series expansion. The random PDE is solved using two…

Numerical Analysis · Mathematics 2021-01-25 Giacomo Capodaglio , Max Gunzburger , Henry P. Wynn

Employing the formalism introduced by Sinai and Yakhot [PRL, 63(18), p. 1962, 1989], we study the probability density functions (pdf's) of decaying passive scalars in periodic domains under the influence of smooth large scale velocity…

Chaotic Dynamics · Physics 2009-11-10 Jai Sukhatme

We investigate the time behavior of the fragmentation model with Kolmogorov time scales and space contraction resembling the random $\beta$-model of turbulence. The space averages computed at any instant using the entire spatial realization…

Condensed Matter · Physics 2007-05-23 Sergei E. Esipov

We present a method for reconstructing cosmological densityn for and velocity fields using the Lagrangian Zel'dovich formalism. . The method involves finding the least action solution for straight line particle paths in an evolving density…

Astrophysics · Physics 2015-06-24 R. A. C. Croft , E. Gaztanaga

We examine several aspects of redshift distortions by expressing the redshift-space density in terms of the eigenvalues and orientation of the local Lagrangian deformation tensor. We explore the importance of multiple-streaming using the…

Astrophysics · Physics 2010-01-15 Lam Hui , Lev Kofman , Sergei F. Shandarin

We introduce a novel two-step approach for estimating a probability density function (pdf) given its samples, with the second and important step coming from a geometric formulation. The procedure involves obtaining an initial estimate of…

Methodology · Statistics 2017-12-14 Sutanoy Dasgupta , Debdeep Pati , Anuj Srivastava

In this work, we studied the impact of galaxy morphology on photometric redshift (photo-$z$) probability density functions (PDFs). By including galaxy morphological parameters like the radius, axis-ratio, surface brightness and the S\'ersic…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-09 John Y. H. Soo , Benjamin Joachimi

In this paper, I present the calculation of the third and fourth moments of both the distribution function of the large--scale density and the large--scale divergence of the velocity field, $\theta$. These calculations are made by the mean…

Astrophysics · Physics 2009-10-22 F. Bernardeau

A new and simple statistical approach is performed to calculate the parton distribution functions (PDFs) of the nucleon in terms of light-front kinematic variables. We do not put in any extra arbitrary parameter or corrected term by hand,…

High Energy Physics - Phenomenology · Physics 2009-03-12 Yunhua Zhang , Lijing Shao , Bo-Qiang Ma