2D BAO vs 3D BAO: solving the Hubble tension with an alternative cosmological model

Understand

Ordinary 3D Baryon Acoustic Oscillations (BAO) data are model-dependent, requiring the assumption of a cosmological model to calculate comoving distances during data reduction.

• Throughout the present-day literature, the assumed model is $\Lambda$CDM.
• However, it has been pointed out in several recent works that this assumption can be inadequate when analyzing alternative cosmologies, potentially biasing the Hubble constant ($H_0$) low, thus contributing to the Hubble tension.
• To address this issue, 3D BAO data can be replaced with 2D BAO data, which is only weakly model-dependent.