Speaker
Prof.
Matteo Forconi
(La Sapienza, University of Rome)
Description
The parameter σ8 is commonly used to quantify the amplitude of matter fluctuations at linear cosmological scales. However, its intrinsic dependence on h can introduce biases and couples the growth and Hubble tensions in an intricate way, when comparing the predictions of different models and/or datasets. For example, the bias found in models with large values of H0 is more prominent, artificially complicating the search for a model that can resolve the Hubble tension without exacerbating the growth tension. To address these challenges, an alternative parameter has been proposed: σ12. In this scenario, the worsening of the growth tension in different cases is much less pronounced than previously thought or may even be nonexistent.
