# Joel Hass

**Professor****Geometry and topology**

Ph.D., 1981, University of California, Berkeley**Refereed publications:** Via Math Reviews

**Web Page: ** http://www.math.ucdavis.edu/~hass/

Email: hass@math.ucdavis.edu

Office: MSB 2222

Phone: 601-4444 x4003

### Research

- Geometry of proteins

- Three dimensional manifolds

- Applied math

- Computational complexity

- Computational geometry and topology

- Differential geometry

- Geometric computation

- Minimal surfaces and bubbles

### Selected publications

**[1]**J. Hass and R. Schlafly. " Double Bubbles Minimize,"

*Annals of Mathematics*,

**151**: 459-515, 2000, matharXiv0003.5157.

**[2]** J. Hass and J. Lagarias, " The number of Reidemeister moves needed for unknotting," *J. Amer. Math. Soc.*, **14**(2): 399-428, 2001,
matharXiv9807.5012.

**[3]** J. Hass, I. Agol, and W.P. Thurston, " The Computational Complexity of Knot Genus and Spanning Area," *Trans. Amer. Math. Soc.*, **358**: 3821-3850, 2005,
matharXiv0205.5057.

**[4]** J. Hass and T. Nowik, " Unknot diagrams requiring a quadratic number of Reidemeister moves to untangle," matharXiv0711.2350.

**[5]** J. Hass, " Families of harmonic maps and stabilization of Heegaard splittings," preprint.

### Books

**[1]** How to Ace Calculus: The Streetwise Guide, by Colin Conrad Adams, Joel Hass, Abigail Thompson. WH Freeman & Co., September, 1998.

**[2]** How to Ace the Rest of Calculus: The Streetwise Guide, by Colin Conrad Adams, Joel Hass, Abigail Thompson. WH Freeman & Co., September, 2001.

**[3]** Proceedings of the Kirbyfest. Held in Berkeley, CA, June 22-26, 1998. Edited by Joel Hass and Martin Scharlemann. Geometry & Topology Monographs, 2. Geometry & Topology Publications, Coventry, 1999. front matter+569 pp. (electronic). 57-06 (00B30).

**[4]** Thomas’ Calculus 11th edition (with Thomas, Weir, Girodano) Addison-Wesley, 2005.

**[5]** Thomas’ Calculus, 11th edition ET (with Thomas, Weir, Girodano) Addison-Wesley, 2005.

**[6]** University Calculus (with Thomas, Weir), Addison-Wesley, 2006.

*Last updated: 2008-02-27*