ΛCDM provides a leading framework in the interpretation of modern cosmology. Nevertheless, the scientific community still struggles with many open problems in cosmology. Among the most noticeable ones, the tension in the Hubble constant H0 is particularly intriguing, prompting a wide range of possible solutions. In the present work, the flat scale-free cosmology (S CDM) of Maeder (2017) is tested for H0 tension in fits to the Pantheon sample of Supernovae Ia. The Pantheon sample is a collection of 1048 SNe Ia, which formally defines H0 = H(0) by extrapolation to redshift zero of data over positive redshifts z > 0. Here, we consider H0k in fits of S CDM over k equally sized bins of sub-samples of mean redshift zk. To quantify a trend in H0k with zk, the results are fit by f(z)=H0′/(1+z)α in the two parameters H0′ and α. This approach tests for model imperfections or data biases by trends that are inconsistent with zero. Our findings show a decreasing trend inconsistent with zero at 5.3σ significance, significantly more so than in ΛCDM. These results are further confirmed in Pantheon+. It appears that a solution to H0 tension is to be found in models with a deceleration parameter q0 < q0,Λ below that of ΛCDM, rather than q0,Λ < q0S < 0 satisfied by S CDM.
A doublet of cosmological models to challenge the H 0 tension in the Pantheon Supernovae Ia catalog
De Simone, B.
Writing – Review & Editing
;Lambiase, G.Writing – Review & Editing
2025
Abstract
ΛCDM provides a leading framework in the interpretation of modern cosmology. Nevertheless, the scientific community still struggles with many open problems in cosmology. Among the most noticeable ones, the tension in the Hubble constant H0 is particularly intriguing, prompting a wide range of possible solutions. In the present work, the flat scale-free cosmology (S CDM) of Maeder (2017) is tested for H0 tension in fits to the Pantheon sample of Supernovae Ia. The Pantheon sample is a collection of 1048 SNe Ia, which formally defines H0 = H(0) by extrapolation to redshift zero of data over positive redshifts z > 0. Here, we consider H0k in fits of S CDM over k equally sized bins of sub-samples of mean redshift zk. To quantify a trend in H0k with zk, the results are fit by f(z)=H0′/(1+z)α in the two parameters H0′ and α. This approach tests for model imperfections or data biases by trends that are inconsistent with zero. Our findings show a decreasing trend inconsistent with zero at 5.3σ significance, significantly more so than in ΛCDM. These results are further confirmed in Pantheon+. It appears that a solution to H0 tension is to be found in models with a deceleration parameter q0 < q0,Λ below that of ΛCDM, rather than q0,Λ < q0S < 0 satisfied by S CDM.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
