This discrepancy is one that many cosmologists have been attempting to solve by changing our current cosmological model.
The research, titled “Symmetry of Cosmological Observables, a Mirror World Dark Sector, and the Hubble Constant,” was published recently in the journal Physical Review Letters.This result opens a new approach to reconciling cosmic microwave background and large-scale structure observations with high values of the Hubble constant H0: Find a cosmological model in which the scaling transformation can be realized without violating any measurements of quantities not protected by the symmetry.If the universe is somehow exploiting this symmetry researchers are led to an extremely interesting conclusion: that there exists a mirror universe very similar to ours but invisible to us except through gravitational impact on our world.“In practice, this scaling symmetry could only be realized by including a mirror world in the model — a parallel universe with new particles that are all copies of known particles,” said Cyr-Racine.“The mirror world idea first arose in the 1990s but has not previously been recognized as a potential solution to the Hubble constant problem.
In addition to searching for missing ingredients in our current cosmological model, researchers are also wondering whether this Hubble constant discrepancy could be caused in part by measurement errors.Reference: “Symmetry of Cosmological Observables, a Mirror World Dark Sector, and the Hubble Constant” by Francis-Yan Cyr-Racine, Fei Ge and Lloyd Knox, 18 May 2022, Physical Review Letters.May 18, 2022May 18, 2022May 18, 2022May 17, 2022