Cosmological constraints from combined probes with the three-point statistics of galaxies at one-loop precision

We present cosmological constraints from a joint analysis including the power spectrum and bispectrum of Baryon Oscillation Spectroscopic Survey (BOSS) galaxies based on the effective field theory of large-scale structure predictions at one-loop order, in combination with cosmic microwave background (CMB) data from Planck, Supernovae from Pantheon+, and baryon acoustic oscillations (BAO) from Extended Baryon Oscillation Spectroscopic Survey (eBOSS) and 6-degree Field galaxy survey (6dF)/Main Galaxy Sample from the Sloan Digital Galaxy Survey I (MGS). Limits on $\mathrm{\ensuremath{\Lambda}}$ cold dark matter model ($\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$) parameters are in good agreement, and on average $\ensuremath{\sim}5%\ensuremath{-}10%$ tighter, compared to former results including similar datasets but no bispectrum. Moreover, we find that galaxies at the three-point level with one-loop precision are decisive for the dark energy equation of state, constrained to be $w=\ensuremath{-}0.975\ifmmode\pm\else\textpm\fi{}0.019$ at 68% CL. This constraint, about 30% tighter than the former determination, is consistent at $\ensuremath{\sim}1.3\ensuremath{\sigma}$ with a cosmological constant. Our analyses illustrate the importance of beyond-two-point statistics at the highest reachable scales in constraining cosmological parameters, and in particular departure from $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$.