English

Quantifying Weighted Morphological Content of Large-Scale Structures via Simulation-Based Inference

Cosmology and Nongalactic Astrophysics 2026-04-14 v2 Machine Learning Computational Physics

Abstract

We perform a simulation-based forecasting analysis to compare the cosmological constraining power of higher-order summary statistics of the large-scale structure, the Minkowski Functionals (MFs) and a class weighted morphological measure known as the Conditional Moments of Derivatives (CMD), with that of the redshift-space halo power spectrum multipoles (PS), with a particular focus on their sensitivity to nonlinear and anisotropic features in redshift space. Our analysis relies on halo catalogs from the Big Sobol Sequence simulations at redshift z=0.5z=0.5, employing a likelihood-free inference framework implemented via neural posterior estimation. At the fiducial Quijote cosmology and for a Gaussian smoothing scale of R=15h1MpcR=15\,h^{-1}\mathrm{Mpc}, CMD provide systematically tighter constraints than MFs. Combining MFs and CMD into a joint estimator improves the precision by 27%5%+9%27\%^{+9\%}_{-5\%} for σ8\sigma_8 and 26%5%+7%26\%^{+7\%}_{-5\%} for Ωm\Omega_{\mathrm{m}} relative to MFs alone, highlighting the complementary anisotropy-sensitive information captured by the CMD in contrast to the scalar morphological content encapsulated by the MFs. We compare the combined statistic MFs+CMD with the PS at matched effective scales (kmax0.16hMpc1k_{\max}\simeq0.16\,h\,\mathrm{Mpc^{-1}}) under three halo-selection conditions: all halos, fixed number density, and mass-selected (M>3×1013h1MM>3\times10^{13}\,h^{-1}M_\odot). In the mass-selected configuration, the (weighted) morphological estimator outperforms the power spectrum by 45%9%+20%45\%^{+20\%}_{-9\%} for σ8\sigma_8 and 43%7%+10%43\%^{+10\%}_{-7\%} for Ωm\Omega_{\mathrm{m}}. We also extend the simulation-based forecast analysis across a continuous range of cosmological parameters and multiple smoothing scales for morphological measures.

Keywords

Cite

@article{arxiv.2511.03636,
  title  = {Quantifying Weighted Morphological Content of Large-Scale Structures via Simulation-Based Inference},
  author = {M. H. Jalali Kanafi and S. M. S. Movahed},
  journal= {arXiv preprint arXiv:2511.03636},
  year   = {2026}
}

Comments

22 pages, 11 figures and 3 tables. Matched to the revised version. Including new results for Power spectrum

R2 v1 2026-07-01T07:23:09.270Z