Constraints on cosmology beyond $\Lambda$CDM with kinetic Sunyaev Zel'dovich velocity reconstruction

Kinetic Sunyaev Zel'dovich velocity reconstruction uses the statistically anisotropic cross-correlation between cosmic microwave background (CMB) temperature anisotropies and a galaxy survey to reconstruct the remotely observed CMB dipole. Using a reconstruction based on data from $\textit{Planck}$ and unWISE, we rule out non-linear Gpc-scale voids, provide the tightest constraint on the intrinsic dipole ($<14 \ {\rm km/s}$ at $68\%$ confidence), rule out matter-radiation isocurvature as an explanation of discrepancies between the measured CMB and galaxy number count dipoles, and constrain the amplitude of local-type primordial non-Gaussianity ($-220\lesssim f_{\rm NL}\lesssim 136$ at $68\%$ confidence) and compensated isocurvature ($-147\lesssim A_{\rm CIP} \lesssim 281$ at $68\%$ confidence). This representative set of constraints on beyond-$\Lambda$CDM scenarios demonstrates the breadth of fundamental science possible with measurements of secondary CMB anisotropies such as the kinetic Sunyaev Zel'dovich effect.