Warner was a
postdoctoral research fellow in
quantum physics at the centre for
nanotechnology at University College London. He left to join
ASI Data Science (now Faculty), a company founded by his brother Marc Warner in 2014, where he is now a commercial principal. Warner was a key figure in the
computer modelling used by
Vote Leave's successful 2016 referendum campaign. Warner was a member of the
Scientific Advisory Group for Emergencies (SAGE) during the
COVID-19 pandemic, with Cummings and 21 others. ==References==