English
Related papers

Related papers: Ensuring Robustness in Training Set Based Global 2…

200 papers

Redshift space distortion (RSD) observed in galaxy redshift surveys is a powerful tool to test gravity theories on cosmological scales, but the systematic uncertainties must carefully be examined for future surveys with large statistics.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Takashi Ishikawa , Tomonori Totani , Takahiro Nishimichi , Ryuichi Takahashi , Naoki Yoshida , Motonari Tonegawa

The development of radiation hydrodynamical methods that are able to follow gas dynamics and radiative transfer self-consistently is key to the solution of many problems in numerical astrophysics. Such fluid flows are highly complex, rarely…

Kernelized Stein discrepancy (KSD), though being extensively used in goodness-of-fit tests and model learning, suffers from the curse-of-dimensionality. We address this issue by proposing the sliced Stein discrepancy and its scalable and…

Machine Learning · Computer Science 2021-03-18 Wenbo Gong , Yingzhen Li , José Miguel Hernández-Lobato

Observations of the redshifted 21-cm signal emitted by neutral hydrogen represent a promising probe of large-scale structure in the universe. However, cosmological 21-cm signal is challenging to observe due to astrophysical foregrounds…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-07 Haochen Wang , Juan Mena-Parra , Tianyue Chen , Kiyoshi Masui

We present a differentiable, end-to-end Bayesian forward modeling framework for line intensity mapping cosmology experiments, with a specific focus on low-frequency radio telescopes targeting the redshifted 21 cm line from neutral hydrogen…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-15 Nicholas Kern

We propose a family of tests to assess the goodness-of-fit of a high-dimensional generalized linear model. Our framework is flexible and may be used to construct an omnibus test or directed against testing specific non-linearities and…

Methodology · Statistics 2019-11-14 Jana Janková , Rajen D. Shah , Peter Bühlmann , Richard J. Samworth

Classification in the sense of similarity is an important issue. In this paper, we study similarity classification in Topological Data Analysis. We define a pseudometric $d_{S}^{(p)}$ to measure the distance between barcodes generated by…

Algebraic Topology · Mathematics 2024-11-18 Jiaxing He , Bingzhe Hou , Tieru Wu , Yang Cao

The cosmological principle is fundamental to the standard cosmological model. It assumes that the Universe is homogeneous and isotropic on very large scales. As the basic assumption, it must stand the test of various observations. In this…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-13 J. P. Hu , Y. Y. Wang , J. Hu , F. Y. Wang

This paper develops a statistical framework for goodness-of-fit testing of volatility functions in McKean-Vlasov stochastic differential equations, which describe large systems of interacting particles with distribution-dependent dynamics.…

Methodology · Statistics 2025-10-15 Akram Heidari , Mark Podolskij

In this study, we train score-based diffusion models to super-resolve gigaparsec-scale cosmological simulations of the 21-cm signal. We examine the impact of network and training dataset size on model performance, demonstrating that a…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-04 Simon Pochinda , Jiten Dhandha , Anastasia Fialkov , Eloy de Lera Acedo

We present new families of goodness-of-fit tests of uniformity on a full-dimensional set $W\subset\R^d$ based on statistics related to edge lengths of random geometric graphs. Asymptotic normality of these statistics is proven under the…

Statistics Theory · Mathematics 2020-07-20 Bruno Ebner , Franz Nestmann , Matthias Schulte

In this work, we test consistency relations between a kinematic probe, the observational Hubble data, and a dynamical probe, the growth rates for cosmic large scale structure, which should hold if general relativity is the correct theory of…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-18 Xiao-Wei Duan , Min Zhou , Tong-Jie Zhang

We present an investigation of the horizon and its effect on global 21-cm observations and analysis. We find that the horizon cannot be ignored when modeling low frequency observations. Even if the sky and antenna beam are known exactly,…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-15 Neil Bassett , David Rapetti , Keith Tauscher , Bang D. Nhan , David D. Bordenave , Joshua J. Hibbard , Jack O. Burns

We combine in a single framework the two complementary benefits of chi^2-template fits and empirical training sets used e.g. in neural nets: chi^2 is more reliable when its probability density functions (PDFs) are inspected for multiple…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Christian Wolf

[...] We present results for the statistics of thermal gas and the shock wave properties for a large volume simulated with three different cosmological numerical codes: the Eulerian total variations diminishing code TVD, the Eulerian…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 F. Vazza , K. Dolag , D. Ryu , G. Brunetti , C. Gheller , H. Kang , C. Pfrommer

The 21-cm line emitted by neutral hydrogen is the most promising probe of the Epoch of Reionization (EoR). Multiple radio interferometric instruments are on the cusp of detecting its power spectrum. It is therefore essential to deliver…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-15 Anshuman Acharya , Enrico Garaldi , Benedetta Ciardi , Qing-bo Ma

Deep neural network training often involves stochastic optimization, meaning each run will produce a different model. This implies that hyperparameters of the training process, such as the random seed itself, can potentially have…

Machine Learning · Statistics 2025-04-17 Sinjini Banerjee , Tim Marrinan , Reilly Cannon , Tony Chiang , Anand D. Sarwate

We introduce a powerful semi-numeric modeling tool, 21cmFAST, designed to efficiently simulate the cosmological 21-cm signal. Our code generates 3D realizations of evolved density, ionization, peculiar velocity, and spin temperature fields,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Andrei Mesinger , Steven Furlanetto , Renyue Cen

Obtaining accurately calibrated redshift distributions of photometric samples is one of the great challenges in photometric surveys like LSST, Euclid, HSC, KiDS, and DES. We present an inference methodology that combines the redshift…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-09 M. M. Rau , C. B. Morrison , S. J. Schmidt , S. Wilson , R. Mandelbaum , Y. Y. Mao

The redshifted 21-cm emission by neutral hydrogen offers a unique tool for mapping structure formation in the early universe in three dimensions. Here we provide the first detailed calculation of the 21-cm emission signal during and after…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Anastasia Fialkov , Abraham Loeb
‹ Prev 1 3 4 5 6 7 10 Next ›