6.849: Geometric Folding Algorithms: Linkages, Origami, Polyhedra (Fall 2012)

Second, we address a few questions concerning:

• Equilateral vs. equiangular vs. obtuse locked 3D chains
• The shape of the ribosome
• HP protein folding NP-hardness proofs

Third, we cover a new result: Flattening fixed angle chains (and min/max flat span) are strongly NP-hard [Demaine & Eisenstat 2011].

Fourth, we cover a fun series of results on polygon (closed chain) reconfiguration via flips, flipturns, deflations, pops, and popturns. [More detail can be found in 2010's Lecture 21.]