Evolution of Cluster Alignments as Evidence of Large-scale Structure Formation in the Universe

TL;DR

This paper demonstrates that galaxy cluster orientations are correlated over very large scales up to 300 Mpc and persist to redshift z=1, providing evidence for the large-scale structure formation consistent with LCDM models.

Contribution

It presents the first observational evidence of galaxy cluster alignments over scales up to 300 Mpc, extending previous findings and supporting large-scale structure formation theories.

Findings

Cluster orientations are correlated over 200-300 Mpc scales.

Alignments are observed up to redshift z=1.

Results are consistent with LCDM cosmological models.

Abstract

The universe's large-scale structure forms a vast, interconnected network of filaments, sheets, and voids known as the cosmic web. For decades, astronomers have observed that the orientations of neighboring galaxy clusters within these elongated structures are often aligned over separations of tens of Mpc. Using the largest available catalog of galaxy clusters, we show for the first time that clusters orientations are correlated over even larger scales, up to 200-300 comoving Mpc, and such alignments are seen to redshifts of at least z = 1. Comparison with numerical simulations suggests that coherent structures on similar scales may be expected in LCDM models.