Disentangling geometry & growth in cosmic neutrino mass constraints: a more physical split and diagnostic
The study introduces a physical split of neutrino mass sum constraints into geometric ($\sum m_{\nu}^{geo}$) and growth ($\sum m_{\nu}^{growth}$) components. Combining CMB lensing and BAO data, the authors find similar 'negative' preferences in both channels, suggesting the tension might stem from geometry or structure growth. The difference between these two measurements is consistent with zero, passing a null test for the standard $\Lambda$CDM model.