Measuring the cosmic ecosystem with weak gravitational lensing

          @misc{ pirsa_PIRSA:25070075,
            doi = {10.48660/25070075},
            url = {https://pirsa.org/25070075},
            author = {},
            keywords = {Cosmology},
            language = {en},
            title = {Measuring the cosmic ecosystem with weak gravitational lensing},
            publisher = {Perimeter Institute},
            year = {2025},
            month = {jul},
            note = {PIRSA:25070075 see, \url{https://pirsa.org}}
          }
          

Abstract

Weak gravitational lensing is the only way to probe the total matter distribution on the scales of galaxies and the surrounding cosmic web. Understanding the dark matter distribution and its link to galaxies is critical not only galaxy formation and evolution, but also to correctly extract the cosmological parameters from weak lensing surveys. I will highlight recent results from the Ultraviolet Near Infrared Optical Northern Survey (UNIONS), a major weak lensing survey of 6000 square degrees of the northern sky, that probe the dark matter distribution around luminous red galaxies, allowing us to see the feedback-affected matter profiles, around galaxy mergers and in filaments of the cosmic web. If time permits, I will discuss prospect for future weak lensing surveys such as Euclid.