The large-scale environment from cosmological simulations I: The baryonic cosmic web

TL;DR

This study uses cosmological simulations to show that baryonic processes minimally affect large-scale cosmic structures, and that gas alone can reliably trace the filamentary cosmic web for cosmological applications.

Contribution

It demonstrates that baryonic effects have negligible impact on large-scale structure classification and confirms gas as a reliable tracer for the cosmic web, facilitating bias-free cosmological studies.

Findings

Baryonic processes minimally impact large-scale structure classification.

Gas alone can effectively trace the filamentary cosmic web.

Results support using gas observations to connect radio surveys with dark matter distributions.

Abstract

Using a series of cosmological simulations that includes one dark-matter-only (DM-only) run, one gas cooling-star formation-supernovae feedback (CSF) run and one that additionally includes feedback from active galactic nuclei (AGNs), we classify the large-scale structures with both a velocity-shear-tensor code (Vweb) and a tidal-tensor code (Pweb). We find that the baryonic processes have almost no impact on large-scale structures -- at least not when classified using aforementioned techniques. More importantly, our results confirm that the gas component alone can be used to infer the filamentary structure of the Universe practically un-biased, which could be applied to cosmology constrains. In addition, the gas filaments are classified with its velocity (Vweb) and density (Pweb) fields, which can theoretically connect to the radio observations, such as HI surveys. This will help us to bias-freely link the radio observations with DM distributions at large scale.