Light-cone mocks demonstrate that analytical corrections for survey-window and integral-constraint effects on PNG in galaxy power spectra lose accuracy below the equality scale and fail when PNG is present, enabling unbiased large-scale measurements.
Cosmological $N$-body simulations with suppressed variance
7 Pith papers cite this work. Polarity classification is still indexing.
7
Pith papers citing it
abstract
We present and test a method that dramatically reduces variance arising from the sparse sampling of wavemodes in cosmological simulations. The method uses two simulations which are fixed (the initial Fourier mode amplitudes are fixed to the ensemble average power spectrum) and paired (with initial modes exactly out of phase). We measure the power spectrum, monopole and quadrupole redshift-space correlation functions, halo mass function and reduced bispectrum at $z=1$. By these measures, predictions from a fixed pair can be as precise on non-linear scales as an average over 50 traditional simulations. The fixing procedure introduces a non-Gaussian correction to the initial conditions; we give an analytic argument showing why the simulations are still able to predict the mean properties of the Gaussian ensemble. We anticipate that the method will drive down the computational time requirements for accurate large-scale explorations of galaxy bias and clustering statistics, enabling more precise comparisons with theoretical models, and facilitating the use of numerical simulations in cosmological data interpretation.
citation-role summary
method 2
background 1
citation-polarity summary
fields
astro-ph.CO 7years
2026 7verdicts
UNVERDICTED 7representative citing papers
DESI DR1 Lyman-alpha data yields Δ²★=0.379±0.032 and n★=-2.309±0.019 at k★=0.009 km⁻¹s and z=3, sharpening N_eff, α_s, and β_s constraints by factors of 1.18-1.90 when combined with other probes.
Galaxy pairwise peculiar velocities from Cosmicflows-4 yield M_ν = 0.24^{+0.34}_{-0.18} eV and η² = 2.14^{+0.30}_{-0.32} (7σ non-zero asymmetry) in the CMB framework, consistent with prior Planck results.
Rescaling merger trees with a halo-profile correction enables cheap generation of galaxy summary statistics across cosmologies using semi-analytic models, matching dedicated simulation accuracy with far fewer base runs.
21cmEMUv3 emulates the cylindrical 21cm power spectrum via score-based diffusion and six other 21cmFAST observables via LSTM networks at sub-percent accuracy, then uses the emulator to infer a lower limit on soft-band X-ray luminosity from HERA data.
First systematic validation shows Hybrid Bias Expansion model for galaxy bispectrum remains accurate up to k=0.25 h/Mpc in DESI-like mocks, outperforming tree-level EFT.
Neighbor-density-weighted marked correlation functions improve FoM for Ω_m–σ_8 by 1.7–2.5× over standard 2PCF using emulators from 129 w0waCDM+∑m_ν simulations.
citing papers explorer
-
Cosmological analysis of the DESI DR1 Lyman alpha 1D power spectrum
DESI DR1 Lyman-alpha data yields Δ²★=0.379±0.032 and n★=-2.309±0.019 at k★=0.009 km⁻¹s and z=3, sharpening N_eff, α_s, and β_s constraints by factors of 1.18-1.90 when combined with other probes.