# Alleviating the Hubble Tension with a Local Void and Transitions of the Absolute Magnitude

**Authors:** Jing-Yi Jia, Jia-Lei Niu, Da-Chun Qiang, Hao Wei  
**arXiv:** [2504.13380](https://arxiv.org/abs/2504.13380)  
**Date:** 2025-04-18  
**Summary page:** https://www.summarizepaper.com/en/paper/2504.13380v1/

## Key points

- The Hubble tension is a significant inconsistency between measurements of the Hubble constant from local observations of Type Ia supernovae (SNIa) and high-redshift observations of the cosmic microwave background (CMB).
- A novel approach involving a local void has been proposed to address this discrepancy, suggesting that our observable universe may be situated within a locally underdense region of space.
- Previous studies have explored the potential of a local void in alleviating the Hubble tension but found it lacking preference over the standard ΛCDM model when considering observational data like the Pantheon SNIa sample and information criteria such as AIC and BIC.
- Authors Jing-Yi Jia, Jia-Lei Niu, Da-Chun Qiang, and Hao Wei investigated transitions in absolute magnitude $M, combined with data from the Pantheon+ SNIa sample alone or with CMB data from Planck 2018, to mitigate the Hubble tension using a local void.
- Findings suggest that incorporating these factors can satisfactorily mitigate the Hubble tension and models incorporating a ΛLTB void are strongly favored by observational constraints.
- This study contributes valuable insights into resolving cosmology's perplexing issues and emphasizes considering alternative scenarios and additional parameters in understanding our universe's nature and evolution.

## Summary

In the field of cosmology, one of the most pressing challenges currently facing researchers is the Hubble tension. This refers to the significant inconsistency between measurements of the Hubble constant from local observations of Type Ia supernovae (SNIa) and those derived from high-redshift observations of the cosmic microwave background (CMB). To address this discrepancy, a novel approach involving a local void has been proposed. The concept behind this approach is based on the idea that our observable universe may be situated within a region of space that is locally underdense. This could lead to an accelerated rate of expansion compared to the average cosmic expansion. Previous studies have explored the potential of a local void in alleviating the Hubble tension but have found it lacking in terms of preference over the standard $\Lambda$CDM model when considering observational data such as the Pantheon SNIa sample and information criteria like AIC and BIC. In their recent work, authors Jing-Yi Jia, Jia-Lei Niu, Da-Chun Qiang, and Hao Wei delve into this topic further by investigating how transitions in absolute magnitude $M$, combined with data from the Pantheon+ SNIa sample alone or in conjunction with CMB data from Planck 2018, could impact efforts to alleviate the Hubble tension using a local void. Their findings suggest that by incorporating these additional factors, it is indeed possible to satisfactorily mitigate the Hubble tension. Furthermore, they demonstrate that models incorporating a $\Lambda$LTB void are strongly favored by observational constraints. This study not only contributes valuable insights into resolving one of cosmology's most perplexing issues but also underscores the importance of considering alternative scenarios and additional parameters in addressing fundamental questions about the nature and evolution of our universe.