The Mira-Titan Universe IV. High Precision Power Spectrum Emulation

Abstract

Modern cosmological surveys are delivering datasets characterized by unprecedented quality and statistical completeness; this trend is expected to continue into the future as new ground- and space-based surveys come online. In order to maximally extract cosmological information from these observations, matching theoretical predictions are needed. At low redshifts, the surveys probe the nonlinear regime of structure formation where cosmological simulations are the primary means of obtaining the required information. The computational cost of sufficiently resolved large-volume simulations makes it prohibitive to run very large ensembles. Nevertheless, precision emulators built on a tractable number of high-quality simulations can be used to build very fast prediction schemes to enable a variety of cosmological inference studies. We have recently introduced the Mira-Titan Universe simulation suite designed to construct emulators for a range of cosmological probes. The suite covers the standard six cosmological parameters $\{{\omega }_m,{\omega }_b,{\sigma }_8,h,n_s,w_0\}$ and, in addition, includes massive neutrinos and a dynamical dark energy equation of state, $\{{\omega }_{\nu },w_a\}$. In this paper we present the final emulator for the matter power spectrum based on 111 cosmological simulations, each covering a (2.1Gpc)${}^3$ volume and evolving 3200${}^3$ particles. An additional set of 1776 lower-resolution simulations and TimeRG perturbation theory results for the power spectrum are used to cover scales straddling the linear to mildly nonlinear regimes. The emulator provides predictions at the two to three percent level of accuracy over a wide range of cosmological parameters and is publicly released as part of this paper.

References in corpus (8)

• Measurements of the Hubble Constant: Tensions in Perspective
• Flowing with Time: a New Approach to Nonlinear Cosmological Perturbations
• The Mira-Titan Universe II: Matter Power Spectrum Emulation
• Cosmic Calibration: Constraints from the Matter Power Spectrum and the Cosmic Microwave Background
• Cosmic Calibration
• Emulation of baryonic effects on the matter power spectrum and constraints from galaxy cluster data
• Farpoint: A High-Resolution Cosmology Simulation at the Gigaparsec Scale
• Why are we still using 3D masses for cluster cosmology?

Cited by in corpus (23)

• The CosmoVerse White Paper: Addressing observational tensions in cosmology with systematics and fundamental physics
• Hyper Suprime-Cam Year 3 Results: Cosmology from Cosmic Shear Power Spectra
• The MillenniumTNG Project: High-precision predictions for matter clustering and halo statistics
• Aemulus $\nu$: Precise Predictions for Matter and Biased Tracer Power Spectra in the Presence of Neutrinos
• Euclid: Modelling massive neutrinos in cosmology -- a code comparison
• CSST Cosmological Emulator I: Matter Power Spectrum Emulation with one percent accuracy to k = 10 h/Mpc
• The e-MANTIS emulator: fast predictions of the non-linear matter power spectrum in $f(R)$CDM cosmology
• Probing massive neutrinos with the Minkowski functionals of the galaxy distribution
• Sesame: A power spectrum emulator pipeline for beyond-$\Lambda$CDM models
• Neural network reconstruction of density and velocity fields from the 2MASS Redshift Survey
• Galaxy Clustering in the Mira-Titan Universe I: Emulators for the redshift space galaxy correlation function and galaxy-galaxy lensing
• Improving initialization and evolution accuracy of cosmological neutrino simulations
• CSST Cosmological Emulator II: Generalized Accurate Halo Mass Function Emulation
• MF-Box: Multi-fidelity and multi-scale emulation for the matter power spectrum
• DESI forecast for Dark Matter-Neutrino interactions using EFTofLSS
• Aemulus $\nu$: Precision halo mass functions in w$\nu$CDM cosmologies
• Design and optimization of neural networks for multifidelity cosmological emulation
• Power Spectrum Emulators from Neural Networks and Tree-Based Methods
• Ten-dimensional neural network emulator for the nonlinear matter power spectrum
• A simple prediction of the nonlinear matter power spectrum in Brans-Dicke gravity from linear theory
• Non-linear infusion of intrinsic alignment and source clustering: impact on non-Gaussian cosmic shear statistics
• Web-Halo Model (WHM): Accurate non-linear matter power spectrum predictions without free parameters
• Slow neutrinos: non-linearity and momentum-space emulation