REVIEW 2 major objections 2 minor 73 references
The radial acceleration relation in galaxies shows a higher characteristic scale at higher redshifts.
Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →
T0 review · grok-4.3
2026-05-08 10:42 UTC pith:DWYW732L
load-bearing objection This paper reports a statistically significant rise in the RAR characteristic scale with redshift from MUSE data at 0.3<z<1.4, but the 3D modeling lacks mock validation against possible z-dependent biases. the 2 major comments →
MUSE-DARK III: The evolution of the radial acceleration relation at intermediate redshifts
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
The radial acceleration relation persists in the intermediate-redshift sample but is offset from the local relation, with a characteristic acceleration scale a0(z~1) = 2.38 ± 0.1 × 10^{-10} m s^{-2} and an intrinsic scatter of ~0.17 dex. When the sample is divided into redshift bins the scale rises systematically with z. Parametrizing the dependence as a0(z) = a0(0) + a1 z yields a1 = 1.59 ± 0.1 × 10^{-10} m s^{-2}, giving evidence for redshift evolution. The same trend is recovered when different dark matter halo profiles are adopted or when the analysis is performed within the Modified Newtonian Dynamics framework.
What carries the argument
Three-dimensional forward modeling of disk-halo decomposition that derives the intrinsic observed and baryonic radial accelerations from MUSE data cubes, including pressure-support corrections.
Load-bearing premise
The three-dimensional forward modeling with disk-halo decomposition accurately recovers the intrinsic accelerations without significant systematic bias from the choice of dark matter halo profile or sample selection.
What would settle it
Independent measurements of the radial acceleration relation at z ~ 1 using a different instrument or modeling pipeline that recover a characteristic scale matching the local value would contradict the reported linear increase with redshift.
If this is right
- The radial acceleration relation continues to exist at lookback times up to roughly eight billion years.
- The characteristic acceleration scale increases linearly with redshift.
- The scatter around the relation is larger than the value measured in the local universe.
- The evolution signal remains when the analysis is repeated with alternate dark matter halo profiles or within the Modified Newtonian Dynamics framework.
Where Pith is reading between the lines
- If the linear rise in the characteristic scale continues, observations at redshifts above 1.5 should show still larger values and would provide a direct test of the trend.
- The increase could reflect higher levels of gas turbulence or different feedback regimes in younger galaxies that alter the effective gravitational acceleration.
- Galaxy formation simulations could be checked against this redshift-dependent shift to see whether they reproduce the changing link between baryons and total acceleration.
Editorial analysis