SLAC, Kavli 3rd Floor Conf. Room
I will start by discussing some recent measurements of low redshift matter fluctuations, showing interesting discrepancies with predictions from the early Universe. I will highlight challenges and potential solutions that serve as cautionary tales and preparatory work for the analysis of Rubin Observatory's data and its joint modeling with CMB and spectroscopic surveys.
I will then discuss how advances in experimental techniques, together with Rubin Observatory's data, make it possible to map the high redshift Universe in three dimensions at high fidelity in the near future. This will increase the observed volume by many-fold, while providing unprecedented access to very large scales, which hold key information about primordial physics. I will highlight the science opportunities of the proposed spectroscopic roadmap, which includes an extension of the DESI survey (DESI-II) as well as Stage-5 spectroscopy, a proposed follow-up to Rubin's LSST. I will explain how these experiments will address fundamental questions related to the origin of primordial fluctuations, the matter and energy content of the Universe and open up a new observational window which greatly enhances the potential for new discoveries.