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Related papers: Non-Gaussian inference from non-linear and non-Poi…

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In gravitational wave astronomy, non-Gaussian noise, such as scattered light noise disturbs stable interferometer operation, limiting the interferometer's sensitivity, and reducing the reliability of the analyses. In scattered light noise,…

General Relativity and Quantum Cosmology · Physics 2024-03-20 Shunsei Yamamura , Hirotaka Yuzurihara , Takahiro Yamamoto , Takashi Uchiyama

We study the indirect detection of dark matter when the local dark matter velocity distribution depends upon position, as expected for the Milky Way and its dwarf spheroidal satellites, and the annihilation cross-section is not purely…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Francesc Ferrer , Daniel R. Hunter

We discuss models of primordial density perturbations where the non-Gaussianity is strongly scale-dependent. In particular, the non-Gaussianity may have a sharp cut-off and be very suppressed on large cosmological scales, but sizeable on…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-18 Antonio Riotto , Martin S. Sloth

We use the spherical evolution approximation to investigate nonlinear evolution from the non-Gaussian initial conditions characteristic of the local f_nl model. We provide an analytic formula for the nonlinearly evolved probability…

Astrophysics · Physics 2009-11-13 Tsz Yan Lam , Ravi K. Sheth

In the standard model for structure formation, bound objects originate from the gravitational collapse of small perturbations arising from quantum fluctuations with random phases. In other scenarios, based on defects, structures are seeded…

Astrophysics · Physics 2009-11-06 Licia Verde , Alan F. Heavens

We investigate whether a Gaussian likelihood, as routinely assumed in the analysis of cosmological data, is supported by simulated survey data. We define test statistics, based on a novel method that first destroys Gaussian correlations in…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-15 Elena Sellentin , Alan F. Heavens

Bayesian imaging inverse problems in astrophysics and cosmology remain challenging, particularly in low-data regimes, due to complex forward operators and the frequent lack of well-motivated priors for non-Gaussian signals. In this paper,…

Instrumentation and Methods for Astrophysics · Physics 2026-02-06 Sébastien Pierre , Erwan Allys , Pablo Richard , Roman Soletskyi , Alexandros Tsouros

Gaussian time-series models are often specified through their spectral density. Such models present several computational challenges, in particular because of the non-sparse nature of the covariance matrix. We derive a fast approximation of…

Computation · Statistics 2012-11-20 Nicolas Chopin , Judith Rousseau , Brunero Liseo

We study Newtonian cosmological perturbation theory from a field theoretical point of view. We derive a path integral representation for the cosmological evolution of stochastic fluctuations. Our main result is the closed form of the…

Astrophysics · Physics 2008-12-18 Keisuke Izumi , Jiro Soda

Galaxies are biased tracers of the underlying cosmic web, which is dominated by dark matter components that cannot be directly observed. Galaxy formation simulations can be used to study the relationship between dark matter density fields…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-19 Victoria Ono , Core Francisco Park , Nayantara Mudur , Yueying Ni , Carolina Cuesta-Lazaro , Francisco Villaescusa-Navarro

Detecting the dark matter annihilation signal from Galactic substructure, or subhalos, is an important challenge for high-energy gamma-ray experiments. In this paper we discuss detection prospects by combining two different aspects of the…

Astrophysics of Galaxies · Physics 2010-12-24 Eric J. Baxter , Scott Dodelson , Savvas M. Koushiappas , Louis E. Strigari

Context. Weak lensing and clustering statistics beyond two-point functions can capture non-Gaussian information about the matter density field, thereby improving the constraints on cosmological parameters relative to the mainstream methods…

We review the field of collisionless numerical simulations for the large-scale structure of the Universe. We start by providing the main set of equations solved by these simulations and their connection with General Relativity. We then…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-14 Raul E. Angulo , Oliver Hahn

Gaussianizing transformations are used statistically in many non-cosmological fields, but in cosmology, we are only starting to apply them. Here I explain a strategy of analyzing the 1-point function (PDF) of a spatial field, together with…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-22 Mark C. Neyrinck

We compute analytically the small-scale temperature fluctuations of the cosmic microwave background from cosmic (super-)strings and study the dependence on the string intercommuting probability $P$. We develop an analytical model which…

We derive cosmological constraints from the probability distribution function (PDF) of evolved large-scale matter density fluctuations. We do this by splitting lines of sight by density based on their count of tracer galaxies, and by…

Using a discrete wavelet based space-scale decomposition (SSD), the spectrum of the skewness and kurtosis is developed to describe the non-Gaussian signatures in cosmologically interesting samples. Because the basis of the discrete wavelet…

Astrophysics · Physics 2007-05-23 Jesus Pando , Li-Zhi Fang

We use simulated maps of the cosmic microwave background anisotropy to quantify the ability of different statistical tests to discriminate between Gaussian and non-Gaussian models. Despite the central limit theorem on large angular scales,…

Astrophysics · Physics 2009-10-31 Nicholas G. Phillips , A. Kogut

One of the most powerful tools to probe the existence of cosmic defects in the early universe is through the Cosmic Microwave Background (CMB) radiation. It is well known that computations with causal sources are more involved than the…

Astrophysics · Physics 2007-05-23 Alejandro Gangui

Non-Gaussian statistics in the distribution of large scale structure, and in temperature fluctuations of the cosmic microwave background, can be used to constrain inflationary models. Data on the cosmic microwave background from Planck…

General Relativity and Quantum Cosmology · Physics 2018-03-06 Nick Woods
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