Twitter Dr. Abdur Chowdhury serves as Twitter’s Chief Scientist. Prior to that, Dr. Chowdhury co-founded Summize, a real-time search engine sold to Twitter in 2008. Dr. Chowdhury has held positions at AOL as their Chief Architect for Search, Georgetown’s Computer Science Department and University of Maryland’s Institute for Systems Research. His research interest lays in Information Retrieval focusing on making information accessible.