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arXiv · 2604.27867

Cosmological Observational Tests in the JWST Era. II: The Tolman Test

V. V. Tsymbal·A. A. Raikov·N. Yu. Lovyagin
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Abstract

In this work, we investigate a classical cosmological test - the dependence of galaxy surface brightness on redshift z (the Tolman test). We analyzed 6 860 galaxies with reliably determined spectroscopic redshifts from the ASTRODEEP-JWST photometric catalogue. We find that (a) the mean surface brightness of galaxies indeed decreases with increasing distance, and (b) the observed trend shows a significant departure from the prediction of the standard cosmological model, which expects the mean surface brightness to decline as ~ (1 + z)^-4.

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V. V. Tsymbal, A. A. Raikov, N. Yu. Lovyagin. 2026-04-30. Cosmological Observational Tests in the JWST Era. II: The Tolman Test. https://arxiv.org/abs/2604.27867

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