Joel Hass

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Joel Hass

Joel Hass is an American mathematician, a professor of mathematics and chair of the mathematics department at the University of California, Davis.[1]


Hass received his Ph.D. from the University of California, Berkeley in 1981 under the supervision of Robion Kirby.[2] He joined the Davis faculty in 1988.[1]

In 2012 he became a fellow of the American Mathematical Society.[3]

Research contributions[edit]

Hass is known for proving the equal-volume special case of the double bubble conjecture,[4] for proving that the unknotting problem is in NP,[5] and for giving an exponential bound on the number of Reidemeister moves needed to reduce the unknot to a circle.[6]

Selected publications[edit]

Research papers


External links[edit]