Fit direction and BAO components
Individual run · T-17e2f3f5880d
Public summary of an internal test, not yet independently validated or published.
Question investigated
Does the direction of the preference for evolving dark energy in Pantheon+, DES-SN5YR and Union3 persist when the BAO groups at the ends and center of the redshift range are excluded, with the prior Ωm = 0.33 ± 0.01?
Test conditions
For each supernova compilation (Pantheon+, DES-SN5YR and Union3), the fit is repeated with one DESI DR2 BAO group excluded at a time. The groups contain measurements at z = (0.295, 2.33); (0.51, 0.706, 0.934, 1.321, 1.484). The adopted prior is Ωm = 0.33 ± 0.01. This grouping belongs to a set of three prespecified partitions; the assumptions and estimator are unchanged.
Result
The direction of the preference for evolving dark energy persisted after each group was excluded. The result demonstrates internal robustness for the data and groupings examined, without establishing a global detection.
Physical interpretation
The test measures the robustness of the preference to the BAO data selection and the supernova compilation. Its scope is internal to this comparison; a global assessment also requires the cosmic microwave background and the structure power spectrum.