In Pantheon+ and DES-SN5YR, with Ωm = 0.33 ± 0.01, does the preference for dynamical dark energy persist after the exclusion of each of the six BAO tracer groups?
Public summary of an internal test, not yet independently validated or published.
Question investigated
In Pantheon+ and DES-SN5YR, with Ωm = 0.33 ± 0.01, does the preference for dynamical dark energy persist after the exclusion of each of the six BAO tracer groups?
Test conditions
Refit Pantheon+ and DES-SN5YR after excluding, one at a time, the 6 DESI BAO groups at z = (0.295); (0.51, 0.706); (0.934); (1.321); (1.484); (2.33). Hold the supernova data and cosmic microwave background constraints fixed. Adopt Ωm = 0.33 ± 0.01. Compare fit quality and shifts in the dark-energy parameters.
Result
The preference for dynamical dark energy retained the same direction in every tested group exclusion. This stability is limited to the analyzed data, priors and groupings; it does not establish a globally significant detection.
Physical interpretation
This test measures how much each BAO tracer group contributes to the cosmological preference. Sensitivity to a group alone does not identify its physical or observational cause.