- Geometry of proteins
- Three dimensional manifolds
- Applied math
- Computational complexity
- Computational geometry and topology
- Differential geometry
- Geometric computation
- Minimal surfaces and bubbles
Selected publications J. Hass and R. Schlafly. " Double Bubbles Minimize," Annals of Mathematics, 151: 459-515, 2000, matharXiv0003.5157.
 J. Hass and J. Lagarias, " The number of Reidemeister moves needed for unknotting," J. Amer. Math. Soc., 14(2): 399-428, 2001, matharXiv9807.5012.
 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.
 J. Hass and T. Nowik, " Unknot diagrams requiring a quadratic number of Reidemeister moves to untangle," matharXiv0711.2350.
 J. Hass, " Families of harmonic maps and stabilization of Heegaard splittings," preprint.
 How to Ace Calculus: The Streetwise Guide, by Colin Conrad Adams, Joel Hass, Abigail Thompson. WH Freeman & Co., September, 1998.
 How to Ace the Rest of Calculus: The Streetwise Guide, by Colin Conrad Adams, Joel Hass, Abigail Thompson. WH Freeman & Co., September, 2001.
 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).
 Thomas’ Calculus 11th edition (with Thomas, Weir, Girodano) Addison-Wesley, 2005.
 Thomas’ Calculus, 11th edition ET (with Thomas, Weir, Girodano) Addison-Wesley, 2005.
 University Calculus (with Thomas, Weir), Addison-Wesley, 2006.
Last updated: 2008-02-27