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This is the third in a series of papers that develop a new and flexible model to predict weak-lensing (WL) peak counts, which have been shown to be a very valuable non-Gaussian probe of cosmology. In this paper, we compare the cosmological…

宇宙学与河外天体物理 · 物理学 2016-10-03 Chieh-An Lin , Martin Kilbinger , Sandrine Pires

We study the impact of primordial non-Gaussianity on the density profile of dark matter halos by using the semi-analytical model introduced recently by Dalal {\it et al.} which relates the peaks of the initial linear density field to the…

宇宙学与河外天体物理 · 物理学 2013-09-17 Azadeh Moradinezhad Dizgah , Scott Dodelson , Antonio Riotto

We present an algorithm to identify sparse dependence structure in continuous and non-Gaussian probability distributions, given a corresponding set of data. The conditional independence structure of an arbitrary distribution can be…

机器学习 · 计算机科学 2017-11-07 Rebecca E. Morrison , Ricardo Baptista , Youssef Marzouk

Primordial non-Gaussianity (NG) affects the large scale structure (LSS) of the universe by leaving an imprint on the distribution of matter at late times. Much attention has been focused on using the distribution of collapsed objects (i.e.…

宇宙学与河外天体物理 · 物理学 2011-02-25 Guido D'Amico , Marcello Musso , Jorge Noreña , Aseem Paranjape

We use the concept of excursions for the prediction of random variables without any moment existence assumptions. To do so, an excursion metric on the space of random variables is defined which appears to be a kind of a weighted…

统计理论 · 数学 2022-09-07 Vitalii Makogin , Evgeny Spodarev

An interesting statistical problem is to find regions where some studied process exceeds a certain level. Estimating such regions so that the probability for exceeding the level in the entire set is equal to some predefined value is a…

统计方法学 · 统计学 2012-11-19 David Bolin , Finn Lindgren

We study the statistical properties of the eigenvalues of the primordial tidal and deformation tensor for random Gaussian cosmic density fields. With the tidal and deformation tensors, Hessians of the gravitational and velocity potential,…

宇宙学与河外天体物理 · 物理学 2023-01-19 Job Feldbrugge , Yihan Yan , Rien van de Weygaert

In recent years, several experiments highlighted a new type of diffusion anomaly, which was called Brownian yet non-Gaussian diffusion. In systems displaying this behavior, the mean squared displacement of the diffusing particles grows…

统计力学 · 物理学 2023-08-01 Adrian Pacheco-Pozo , Igor M. Sokolov

We investigate the problem of predicting the halo mass function from the properties of the Lagrangian density field. We focus on a perturbation spectrum with a small-scale cut-off (as in warm dark matter cosmologies). This cut-off results…

宇宙学与河外天体物理 · 物理学 2015-06-16 Oliver Hahn , Aseem Paranjape

In the standard excursion set model for the growth of structure, the statistical properties of halos are governed by the halo mass and are independent of the larger scale environment in which the halos reside. Numerical simulations,…

宇宙学与河外天体物理 · 物理学 2015-06-18 Jun Zhang , Chung-Pei Ma , Antonio Riotto

Peak counts have been shown to be an excellent tool to extract the non-Gaussian part of the weak lensing signal. Recently, we developped a fast stochastic forward model to predict weak-lensing peak counts. Our model is able to reconstruct…

宇宙学与河外天体物理 · 物理学 2015-11-16 Chieh-An Lin , Martin Kilbinger

The severity of multivariate extreme events is driven by the dependence between the largest marginal observations. The H\"usler-Reiss distribution is a versatile model for this extremal dependence, and it is usually parameterized by a…

统计方法学 · 统计学 2023-10-16 Manuel Hentschel , Sebastian Engelke , Johan Segers

We present an analytical model for the non-spherical collapse of overdense regions out of a Gaussian random field of initial cosmological perturbations. The collapsing region is treated as an ellipsoid of constant density, acted upon by the…

天体物理学 · 物理学 2009-10-22 Daniel J. Eisenstein , Abraham Loeb

We present an efficient algorithm to compute tight upper bounds of collision probability between two objects with positional uncertainties, whose error distributions are represented with non-Gaussian forms. Our approach can handle noisy…

机器人学 · 计算机科学 2019-12-17 Jae Sung Park , Dinesh Manocha

Digital co-addition of astronomical images is a common technique for increasing signal-to-noise and image depth. A modification of this simple technique has been applied to the detection of minor bodies in the Solar System: first stationary…

地球与行星天体物理 · 物理学 2015-05-18 Alex H. Parker , JJ. Kavelaars

We develop a practical framework for distinguishing diffusive stochastic processes from deterministic signals using only a single discrete time series. Our approach is based on classical excursion and crossing theorems for continuous…

机器学习 · 统计学 2026-05-19 Sunia Tanweer , Firas A. Khasawneh

Excursion set theory (EST) is an analytical framework to study the large-scale structure of the Universe. EST introduces a procedure to calculate the number density of structures by relating the cosmological linear perturbation theory to…

宇宙学与河外天体物理 · 物理学 2017-09-06 Farnik Nikakhtar , Shant Baghram

Corrections induced by primordial non-Gaussianity to the linear halo bias can be computed from a peak-background split or the widespread local bias model. However, numerical simulations clearly support the prediction of the former, in which…

宇宙学与河外天体物理 · 物理学 2015-06-12 Vincent Desjacques , Jinn-Ouk Gong , Antonio Riotto

We present preliminary results of our investigation into the influence of shear fields on the evolution of galactic scale fluctuations in a primordial Gaussian random density field. Specifically, we study how the matter associated with a…

天体物理学 · 物理学 2009-10-22 Rien van de Weygaert , Arif Babul

We study percolative properties of excursion processes and the discrete Gaussian free field (dGFF) in the planar unit disk. We consider discrete excursion clouds, defined using random walks as a two-dimensional version of random…