Physics and Astronomy Colloquium: “Pursuing cosmic puzzles with galaxy surveys”

Bhuvnesh Jain (University of Pennsylvania)
- | Zoom link below

The universe is expanding faster than any reasonable theoretical prediction! This challenge to the standard model of cosmology frames the interpretation of the Dark Energy Survey and other massive datasets. I will show the empirical results that led to this puzzle and new measurement of gravitational lensing that pose a second challenge for theorists: the level of inhomogeneities in the universe is smaller than expected. The possible resolutions of these cosmic puzzles involve revisions to our understanding of dark energy, dark matter or gravity itself. Statistical advances and clever algorithms are a major part of this story. They enable additional tests of novel physics on the much smaller scales of individual clusters, galaxies and stars. I will show how we have established the boundary of the dark matter ‘halos’ of galaxy clusters, which offers a new probe of dark matter and gravity. 

Recording of talk: https://upenn.zoom.us/rec/share/-i_q14l9aFuMqKKH6svNTZ1We1we2KRCQB8sdeRaE-KfbL_kUniWOKdDpikcFRd_.vtXYzCV-_64wf7Ul  

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