Robustness of void statistics to systematics and algorithm choices

Determine whether the statistical properties of cosmic voids are intrinsically robust or are significantly shaped by observational systematics and by the definitions imposed by different void-finding algorithms, in order to establish the reliability of void-based cosmological inferences.

Background

Cosmic voids encode information about large-scale structure formation and are widely used to test cosmology. However, their measured statistics can be influenced by observational effects such as redshift-space distortions and by the specific definitions adopted by different void-finding algorithms (e.g., sphere-based versus watershed-based methods).

A key question motivating this work is whether observed void statistics reflect intrinsic properties of the matter distribution or are substantially modulated by these systematics and methodological choices. The paper investigates this by comparing SDSS observations with ELUCID constrained simulations across multiple void finders.

References

Despite these extensive efforts, it remains unclear whether the statistical properties of cosmic voids are intrinsically robust, or to what extent they are shaped by observational systematics and algorithmic definitions.

— Robustness of cosmic void statistics: insights from SDSS DR7 and the ELUCID simulation  (2603.29706 - Zhang et al., 31 Mar 2026) in Introduction (Section 1)