Document Type
Article
Publication Date
4-29-2025
Published In
Physical Review D
Abstract
The cosmic calibration tension is a >5�� discrepancy between the cosmological distance ladder built from baryonic acoustic oscillations calibrated by the Planck/Λ cold dark matter (ΛCDM) sound horizon (����) and type Ia supernovae calibrated instead with the SH0ES absolute magnitude, assuming the distance-duality relationship holds. In this work, we emphasize the consequences of this tension beyond the value of the Hubble constant ��₀ and the implications for physics beyond ΛCDM. Of utmost importance, it implies a larger physical matter density ��ₘ≡Ωₘℎ², as both the fractional matter density Ωₘ and ℎ ≡��₀/100 km/s/Mpc are well constrained from late-time data. New physics in the prerecombination era must thus be able to decrease ���� while either reducing the value of Ωₘ or increasing the value of ��ₘ. Assuming a ΛCDM-like primordial power spectrum, this necessarily results in an increase in the clustering amplitude ��₈. Deviations from ΛCDM in the late-time expansion history cannot resolve the calibrator tension but can help relax the required shifts to the matter density and ��₈: it is in that sense that a combination of early- and late-time new physics may help alleviate the tension. More precisely, models that modify the prerecombination expansion history can accommodate the increase in ��m without the need for additional modifications. It is those models which only affect recombination that require additional deviations at late times to be successful. Hence, the cosmic calibration tension points either to a targeted modification of the prerecombination expansion history or to a broader change affecting multiple cosmic epochs.
Recommended Citation
V. Poulin et al.
(2025).
"Implications Of The Cosmic Calibration Tension Beyond ��₀ And The Synergy Between Early- And Late-Time New Physics".
Physical Review D.
Volume 111,
DOI: 10.1103/PhysRevD.111.083552
https://works.swarthmore.edu/fac-physics/562
Comments
This work is freely available courtesy of the American Physical Society.