English

Measurement of the Weyl Potential Evolution and $E_G$ Statistic from KiDS-1000, BOSS and 2dFLenS

Cosmology and Nongalactic Astrophysics 2026-04-28 v1

Abstract

A recently developed model-independent approach to measuring the Weyl potential has shown some tensions with Λ\LambdaCDM (Lambda Cold Dark Matter) in DES (Dark Energy Survey) Y3 data. We apply this framework to Kilo-Degree Survey (KiDS-1000) weak lensing and BOSS/2dFLenS galaxy clustering using the KiDS Cosmology Analysis Pipeline (KCAP) in two redshift bins. Without external CMB priors, both the Weyl potential and EGE_G measurements are consistent with late time constraints. After imposing Planck18 priors, the low redshift bin remains compatible with General Relativity, whereas the high redshift bin shows a weaker Weyl potential and lower EGE_G, corresponding to a mild 1.52σ1.52\sigma deviation from the Λ\LambdaCDM cosmology. Furthermore, phenomenological modified gravity models show a mild preference for a suppressed high redshift Weyl potential, but late time data alone remain consistent with Λ\LambdaCDM. Our results also suggest that this deviation is primarily driven by the specific high redshift CMASS sample, reflecting the well-known ``Lensing is low'' problem.

Keywords

Cite

@article{arxiv.2604.24631,
  title  = {Measurement of the Weyl Potential Evolution and $E_G$ Statistic from KiDS-1000, BOSS and 2dFLenS},
  author = {Xuwei Zhang and Ming Zhang and Yunliang Ren and Xiaofeng Yang},
  journal= {arXiv preprint arXiv:2604.24631},
  year   = {2026}
}

Comments

16 pages, 4 figures