Tim joined Steward Observatory in August 2018. His research focusses on testing models of cosmological structure formation (dark energy, dark matter, modified gravity) through statistical data analysis. He is interested in optimally extracting the cosmological information from ongoing and future datasets such as the Dark Energy Survey, the Dark Energy Spectroscopic Instrument, Rubin Observatory, the NASA SPHEREx explorer satellite, the Nancy Grace Roman Space Telescope, and future CMB experiments. A key element of his research is to combine multiple probes and measurements, e.g. weak lensing, galaxy clustering, galaxy clusters and CMB lensing.

Tim got his PhD in 2009 from the University of Bonn, Germany. He held postdoctoral positions at the Ohio State University and the University of Pennsylvania before becoming a staff scientist at NASA-JPL and then faculty at UArizona.