NECOLA: Toward a Universal Field-level Cosmological Emulator
Document Type
Article
Publication Date
5-10-2022
Department
Department of Physics
Abstract
We train convolutional neural networks to correct the output of fast and approximate N-body simulations at the field level. Our model, Neural Enhanced COLA (NECOLA), takes as input a snapshot generated by the computationally efficient COLA code and corrects the positions of the cold dark matter particles to match the results of full N-body Quijote simulations. We quantify the accuracy of the network using several summary statistics, and find that NECOLA can reproduce the results of the full N-body simulations with subpercent accuracy down to k ≃ 1 hMpc-1. Furthermore, the model that was trained on simulations with a fixed value of the cosmological parameters is also able to correct the output of COLA simulations with different values of ωm, ωb, h, n s , σ 8, w, and M ν with very high accuracy: the power spectrum and the cross-correlation coefficients are within ≃1% down to k = 1 hMpc-1. Our results indicate that the correction to the power spectrum from fast/approximate simulations or field-level perturbation theory is rather universal. Our model represents a first step toward the development of a fast field-level emulator to sample not only primordial mode amplitudes and phases, but also the parameter space defined by the values of the cosmological parameters.
Publication Title
Astrophysical Journal
Recommended Citation
Kaushal, N.,
Villaescusa-Navarro, F.,
Giusarma, E.,
Li, Y.,
Hawry, C.,
&
Reyes, M.
(2022).
NECOLA: Toward a Universal Field-level Cosmological Emulator.
Astrophysical Journal,
930(2).
http://doi.org/10.3847/1538-4357/ac5c4a
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p/16233
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Version
Publisher's PDF
Publisher's Statement
© 2022. The Author(s). Published by the American Astronomical Society. Publisher’s version of record: https://doi.org/10.3847/1538-4357/ac5c4a