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Related papers: Fast, high-fidelity Lyman $\alpha$ forests with co…

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We present and test a framework that models the three-dimensional distribution of mass in the Universe as a function of cosmological and astrophysical parameters. Our approach combines two different techniques: a rescaling algorithm that…

We present a new latent model of natural images that can be learned on large-scale datasets. The learning process provides a latent embedding for every image in the training dataset, as well as a deep convolutional network that maps the…

Computer Vision and Pattern Recognition · Computer Science 2018-11-06 ShahRukh Athar , Evgeny Burnaev , Victor Lempitsky

Upcoming 21cm surveys will map the spatial distribution of cosmic neutral hydrogen (HI) over very large cosmological volumes. In order to maximize the scientific return of these surveys, accurate theoretical predictions are needed.…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-29 Digvijay Wadekar , Francisco Villaescusa-Navarro , Shirley Ho , Laurence Perreault-Levasseur

Recent Lyman-$\alpha$ forest tomography measurements of the intergalactic medium (IGM) have revealed a wealth of cosmic structures at high redshift ($z\sim 2.5$). In this work, we present the Tomographic Absorption Reconstruction and…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-18 Benjamin Horowitz , Khee-Gan Lee , Martin White , Alex Krolewski , Metin Ata

We investigate the potential of low-redshift Lyman alpha (Ly$\alpha$) forest for constraining active galactic nuclei (AGN) feedback models by analyzing the Illustris and IllustrisTNG simulation at z=0.1. These simulations are ideal for…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-22 Vikram Khaire , Teng Hu , Joseph F. Hennawi , Michael Walther , Frederick Davies

We derive an effective field theory (EFT) for cosmological Lyman alpha forest fluctuations valid for the power spectrum at the one-loop order. The ``bottom-up'' EFT expansion at the level of the transmitted flux is identical to the…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-04 Mikhail M. Ivanov

The correlation between Lyman-alpha absorption in the spectra of quasar pairs can be used to measure the transverse distance scale at z~2, which is sensitive to the cosmological constant (Omega_Lambda) or other forms of vacuum energy. Using…

Astrophysics · Physics 2009-11-07 Patrick McDonald

We present a method to recover the shape and amplitude of the power spectrum of mass fluctuations, P(k), from observations of the high redshift \lya forest. The method is motivated by the physical picture of the \lya forest that has emerged…

Astrophysics · Physics 2009-10-30 Rupert A. C. Croft , David H. Weinberg , Neal Katz , Lars Hernquist

Porting state of the art deep learning algorithms to resource constrained compute platforms (e.g. VR, AR, wearables) is extremely challenging. We propose a fast, compact, and accurate model for convolutional neural networks that enables…

Computer Vision and Pattern Recognition · Computer Science 2017-06-14 Hessam Bagherinezhad , Mohammad Rastegari , Ali Farhadi

We implement the hydro-PM (HPM) technique (Gnedin & Hui 1998) in the hydrodynamical simulation code GADGET-II and quantify the differences between this approximate method and full hydrodynamical simulations of the Lyman-alpha forest in a…

Astrophysics · Physics 2009-11-11 Matteo Viel , Martin G. Haehnelt , Volker Springel

We revisit techniques for performing cosmological simulations with both baryons and cold dark matter when each fluid has different initial conditions, as is the case at the end of the radiation era. Most simulations do not reproduce the…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-17 Simeon Bird , Yu Feng , Christian Pedersen , Andreu Font-Ribera

Semi-analytic methods can generate baryon-corrected fields from N-body simulations (``baryonification'') and are rapidly becoming a ubiquitous tool in modeling structure formation on non-linear scales. We extend this formalism to…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-12 Dhayaa Anbajagane , Shivam Pandey , Chihway Chang

We train a deep convolutional neural network to predict hydrodynamic results for flow coefficients, average transverse momenta and charged particle multiplicities in ultrarelativistic heavy-ion collisions from the initial energy density…

High Energy Physics - Phenomenology · Physics 2023-03-09 H. Hirvonen , K. J. Eskola , H. Niemi

A sample of 8 QSOs with 1.7 < z_em < 3.7 has been observed with VLT/UVES at a typical resolution 45000 and S/N~40-50. Thanks to the two-arm design of the spectrograph, a remarkable efficiency has been achieved below 400nm and above 800nm,…

Astrophysics · Physics 2007-05-23 S. Cristiani , S. Bianchi , S. D'Odorico , T. -S. Kim

Since loose-fitting clothing contains dynamic modes that have proven to be difficult to predict via neural networks, we first illustrate how to coarsely approximate these modes with a real-time numerical algorithm specifically designed to…

Graphics · Computer Science 2024-04-29 Yongxu Jin , Dalton Omens , Zhenglin Geng , Joseph Teran , Abishek Kumar , Kenji Tashiro , Ronald Fedkiw

We present results from end-to-end simulations of observations designed to constrain the rate of change in the expansion history of the Universe using the redshift drift of the Lyman-$\alpha$ forest absorption lines along the lines-of-sight…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-19 Chenxing Dong , Anthony Gonzalez , Stephen Eikenberry , Sarik Jeram , Manunya Likamonsavad , Jochen Liske , Deno Stelter , Amanda Townsend

The remarkable efficiency of the UVES spectrograph at the VLT has made it possible to push high-resolution, high-S/N ground observations of the Ly-a forest down to z~1.5, gaining new insight into the physical conditions of the intergalactic…

Astrophysics · Physics 2009-11-07 S. Cristiani , S. Bianchi , S. D'Odorico , T. -S. Kim

We tackle the challenging problem of creating full and accurate three dimensional reconstructions of botanical trees with the topological and geometric accuracy required for subsequent physical simulation, e.g. in response to wind forces.…

Computer Vision and Pattern Recognition · Computer Science 2018-12-24 Ed Quigley , Winnie Lin , Yilin Zhu , Ronald Fedkiw

We make forecasts for the constraining power of the 1D Wavelet Scattering Transform (WST) when used with a Lyman-$\alpha$ forest cosmology survey. Using mock simulations and a Fisher matrix, we show that there is considerable cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-05 Hurum Maksora Tohfa , Simeon Bird , Ming-Feng Ho , Mahdi Qezlou , Martin Fernandez

We present precision measurements of the bias parameters of the one-loop power spectrum model of the Lyman-alpha (Lya) forest, derived within the effective field theory of large-scale structure (EFT). We fit our model to the…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-26 Roger de Belsunce , Shi-Fan Chen , Mikhail M. Ivanov , Corentin Ravoux , Solene Chabanier , Jean Sexton , Zarija Lukic
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