Speaker
Description
Early dark energy (EDE) alleviates the H_0 tension at the cost of increasing the clustering amplitude and worsening the $S_8$ discrepancy. Motivated by massive neutrinos' ability to suppress structure, we study their impact on EDE combining Planck and BOSS full-shape clustering data. A Bayesian analysis returns no evidence for a non-zero neutrino mass sum $M_{\nu}$ ($<0.15,{\rm eV}$ at 95%~C.L.), with limits driven primarily by shifts in the BAO scale. A frequentist profile likelihood analysis reveals a correlation between $M_{\nu}$ and the EDE fraction $f_{\rm EDE}$, which keeps $H_0$ fixed as $M_\nu$ increases. Compared to the best-fit baseline EDE model ($M_\nu = 0.06,{\rm eV}$), a model with $M_\nu=0.15,{\rm eV}$ maintains the same $H_0$(km/s/Mpc)=(70.08, 70.12, respectively) whilst decreasing $S_8$=(0.837, 0.831 respectively), whilst still representing a better fit ($\Delta \chi^2=-3.1$) relative to $\Lambda$CDM. Our results indicate that an EDE+$M_{\nu}$ model can keep the $H_0$ tension at the same level as baseline EDE while mitigating the enhanced clustering issue.
