Short answers, pulled from the story.
David Gilbert Christian, born on the 30th of June, 1946, in Brooklyn, New York, is a British-American historian originally specialising in Russian history who became internationally recognised for founding and promoting the academic discipline of Big History. He is credited with coining the term Big History and serves as president of the International Big History Association.
Big History is a multidisciplinary field that frames human history within cosmic, geological, and biological timescales, spanning almost fourteen billion years from the Big Bang to the present. David Christian began teaching the first course on the subject in 1989 at Macquarie University in Sydney, drawing on scholarship from biology, cosmology, astronomy, geology, and anthropology.
Maps of Time, published in 2005 by the University of California Press, is a six-hundred-page work that mirrors the content of Christian's Big History course. A reviewer described it as a remarkable work of synthesis and scholarship, and it won the World History Association Book Prize in 2005.
Bill Gates encountered David Christian's Big History course through The Teaching Company's Great Courses series, where it became a best-seller. Gates presented Christian at the TED 2011 Conference in Long Beach, California, and provided funding to help Christian develop a programme bringing the course to secondary-school students in Australia and the United States.
Christian taught at Macquarie University in Sydney from 1975 to 2000, transferred to San Diego State University in California in 2001, and returned to Macquarie in 2009. He also holds teaching affiliations with the University of Vermont and Ewha Womans University in Seoul, and was named a Distinguished Professor at Macquarie in 2014.
Christian's Big History publications include Maps of Time: An Introduction to Big History (2005, University of California Press), Big History: Between Nothing and Everything (2014, McGraw-Hill Education, co-written with Cynthia Stokes Brown and Craig Benjamin), Origin Story: A Big History of Everything (2018, Little, Brown and Company), and Future Stories: What's Next (2022, Little, Brown Spark).