1 code implementation • 27 Feb 2024 • Deaglan J. Bartlett, Benjamin D. Wandelt, Matteo Zennaro, Pedro G. Ferreira, Harry Desmond
Our symbolic expressions for $k_\sigma$, $n_{\rm eff}$ and $C$ have root mean squared fractional errors of 0. 8%, 0. 2% and 0. 3%, respectively, for redshifts below 3 and a wide range of cosmologies.
1 code implementation • 27 Nov 2023 • Deaglan J. Bartlett, Lukas Kammerer, Gabriel Kronberger, Harry Desmond, Pedro G. Ferreira, Benjamin D. Wandelt, Bogdan Burlacu, David Alonso, Matteo Zennaro
We obtain an analytic approximation to the linear power spectrum with a root mean squared fractional error of 0. 2% between $k = 9\times10^{-3} - 9 \, h{\rm \, Mpc^{-1}}$ and across a wide range of cosmological parameters, and we provide physical interpretations for various terms in the expression.
no code implementations • 5 Oct 2023 • T. Lucas Makinen, Justin Alsing, Benjamin D. Wandelt
Set-based learning is an essential component of modern deep learning and network science.
1 code implementation • 18 May 2023 • Niall Jeffrey, Benjamin D. Wandelt
Multiple real-world and synthetic examples illustrate that Evidence Networks are explicitly independent of dimensionality of the parameter space and scale mildly with the complexity of the posterior probability density function.
1 code implementation • 11 Jul 2022 • T. Lucas Makinen, Tom Charnock, Pablo Lemos, Natalia Porqueres, Alan Heavens, Benjamin D. Wandelt
We a) demonstrate the high sensitivity of modular graph structure to the underlying cosmology in the noise-free limit, b) show that graph neural network summaries automatically combine mass and clustering information through comparisons to traditional statistics, c) demonstrate that networks can still extract information when catalogues are subject to noisy survey cuts, and d) illustrate how nonlinear IMNN summaries can be used as asymptotically optimal compressed statistics for Bayesian simulation-based inference.
no code implementations • 11 Nov 2020 • Francisco Villaescusa-Navarro, Benjamin D. Wandelt, Daniel Anglés-Alcázar, Shy Genel, Jose Manuel Zorrilla Mantilla, Shirley Ho, David N. Spergel
For this data, we show that neural networks can 1) extract the maximum available cosmological information, 2) marginalize over baryonic effects, and 3) extract cosmological information that is buried in the regime dominated by baryonic physics.
Cosmology and Nongalactic Astrophysics Astrophysics of Galaxies Instrumentation and Methods for Astrophysics
2 code implementations • 11 Nov 2020 • Niall Jeffrey, Benjamin D. Wandelt
High-dimensional probability density estimation for inference suffers from the "curse of dimensionality".
1 code implementation • 10 Mar 2020 • Florent Leclercq, Baptiste Faure, Guilhem Lavaux, Benjamin D. Wandelt, Andrew H. Jaffe, Alan F. Heavens, Will J. Percival, Camille Noûs
Existing cosmological simulation methods lack a high degree of parallelism due to the long-range nature of the gravitational force, which limits the size of simulations that can be run at high resolution.
Cosmology and Nongalactic Astrophysics Instrumentation and Methods for Astrophysics
1 code implementation • 15 Jan 2020 • Doogesh Kodi Ramanah, Tom Charnock, Francisco Villaescusa-Navarro, Benjamin D. Wandelt
We present an extension of our recently developed Wasserstein optimized model to emulate accurate high-resolution features from computationally cheaper low-resolution cosmological simulations.
Cosmology and Nongalactic Astrophysics
1 code implementation • 19 Dec 2019 • Stephen M. Feeney, Benjamin D. Wandelt, Melissa K. Ness
With this in mind, we introduce SSSpaNG: a data-driven Gaussian Process model of stellar spectra.
Solar and Stellar Astrophysics Astrophysics of Galaxies Instrumentation and Methods for Astrophysics
1 code implementation • 13 Sep 2019 • Tom Charnock, Guilhem Lavaux, Benjamin D. Wandelt, Supranta Sarma Boruah, Jens Jasche, Michael J. Hudson
Here we demonstrate a method for determining the halo mass distribution function by learning the tracer bias between density fields and halo catalogues using a neural bias model.
Cosmology and Nongalactic Astrophysics Instrumentation and Methods for Astrophysics
4 code implementations • 10 Feb 2018 • Tom Charnock, Guilhem Lavaux, Benjamin D. Wandelt
We anticipate that the automatic physical inference method described in this paper will be essential to obtain both accurate and precise cosmological parameter estimates from complex and large astronomical data sets, including those from LSST and Euclid.
Instrumentation and Methods for Astrophysics
1 code implementation • 2 Dec 2007 • William A. Fendt, Benjamin D. Wandelt
This paper presents the second release of Pico (Parameters for the Impatient COsmologist).
1 code implementation • 29 Jun 2006 • William A. Fendt, Benjamin D. Wandelt
In this paper, we demonstrate that using Pico to compute power spectra and likelihoods produces parameter posteriors that are very similar to those using CAMB and the official WMAP3 code, but in only a fraction of the time.
astro-ph
no code implementations • 16 Aug 2000 • Benjamin D. Wandelt, Krzysztof M. Gorski
We propose fast, exact and efficient algorithms for the convolution of two arbitrary functions on the sphere which speed up computations by a factor \order{\sqrt{N}} compared to present methods where $N$ is the number of pixels.
astro-ph