James Hartle

James Burkett Hartle (August 17, 1939 – May 17, 2023) was an American theoretical physicist known for his work in general relativity, astrophysics, and interpreting quantum mechanics. He was one of the pioneers of quantum cosmology. He joined the faculty of the University of California, Santa Barbara in 1966, and was a member of the external faculty of the Santa Fe Institute.

Early life and education Hartle was born on August 17, 1939, in Baltimore, Maryland, to Anna Elizabeth Burkett and Charles James Hartle, who worked for IBM. His father's job required the family to relocated multiple times while Hartle was growing up. He attended public schools in Ohio and Connecticut, as well as the Gilman School in Baltimore.

Hartle then turned his attention towards astrophysics. They discovered the Hartle–Thorne metric, an approximate solution which describes the exterior of a slowly and rigidly rotating, stationary and axially symmetric body.

Funded by an award from the Sloan Foundation, Hartle spent a year at the Institute for Theoretical Astronomy at the University of Cambridge, where he met Stephen Hawking, with whom he became a long-time collaborator. the same conclusion Hawking himself had reached two years earlier. Their work on the thermodynamics of black holes led to the development of the Euclidean approach to quantum gravity. Reviewers have praised the book for its lucid explanations and focus on physical insight rather than mathematical details. Only requires familiarity with calculus and differential equations, making the book suitable for junior or senior undergraduates in physics. He explained his vision for teaching general relativity to undergraduates in a 2006 article.

Hartle was a founder of the Kavli Institute for Theoretical Physics at UC Santa Barbara and served as its director from 1995 to 1997.

He was elected to the American Philosophical Society in 2016. He was also a Fellow of the American Physical Society (APS), a Guggenheim Fellow, and was elected to the National Academy of Sciences. He received the 2009 Einstein Prize from the APS for his "broad range of fundamental contributions to relativistic stars, quantum fields in curved spacetime, and especially quantum cosmology."

Personal life Hartle married Mary Jo Wheeler, a niece of John Archibald Wheeler, in 1984.