Current estimations of cosmological parameters depend often on assumptions about the cosmological model itself. The estimates of H0 or Ωm from CMB surveys, for instance, are valid only assuming a particular model, typically the standard ΛCDM. Similar model-dependent results are obtained also from analyses of large-scale structure. In some case it is however possible to combine observations in such a way to get estimates of physical quantities that are valid regardless (to some extent) of the underlying model.
Here I will discuss how one can determine the cosmological expansion rate H(z) and the deviation from Einstein gravity η by combining in a model-independent way several observational probes, from redshift distortions, to lensing, to matter clustering.
This Friday colloquium will be hybrid. Attendees can therefore participate either in-person or via Zoom. Please join via Zoom at
https://uio.zoom.us/j/69001043754?pwd=cEJpbVE5ci9PdWNtRld2TDNNcGtKdz09
Meeting ID:690 0104 3754
Passcode: PeiseStua3
Attendees will be muted during the colloquium, but will have the opportunity to ask questions at the end by clicking on the "raise hand” button (or send a request via chat).