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arXiv · 2506.07774

Redshift ~2.7 is not special

Prajwel Joseph
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Abstract

Galikyan et al. (2025) reported a statistically significant change in galaxy spectral properties at redshift $z$ $\simeq$ 2.7 based on a Kolmogorov Stochasticity Parameter analysis of JWST spectroscopic data of galaxies. In this comment, we demonstrate that their result is critically driven by a single outlier in the dataset. This outlier arises from the use of a questionable redshift estimate for one spectrum. When the outlier is removed or the redshift is corrected, the claimed transition at $z$ $\simeq$ 2.7 disappears entirely. By independently reproducing their analysis, we demonstrate that the claimed feature is not a robust statistical signal, but an artefact of this anomalous data point.

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Prajwel Joseph. 2025-06-09. Redshift ~2.7 is not special. https://doi.org/10.1051/0004-6361%2F202555988

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