¶ Unzipping Angle
← Unzipping Angle: Tetrahelix | Unzipping Angle Tetrahelix →
Index Entry
Tetrahelix:
“We see three such columns [tetrahelixes] and we see they tend to nest into one another. If you make three of them they do nest very neatly, but when they nest together they bring about a condition where around one vertex-- if they are really nested down well-- we get five tetrahedra around one common axis. We know that if we take a tetrahedron that its edge angle is 70 degrees and 32 minutes and five times that is about six degrees less than 360 degrees. In other words, five tetrahedra round a common edge axis do not close up and make 360 degrees, but when we bring them together in a helix like this-- due to the fact that the helix is a spring, the total helix as a spring will contract enough to allow these five to connect, because part of the five are in one column and part of the five in another column. The sets of springs will collapse enough; and no matter how long they are we find that these springs will collapse and let them come together. You are doing it against the spring and they are on the spring so therefore they would like to tear it apart.”
TETRAHELIX - SEC. 944.01 (Gray) f 944.03 (Gray)
¶ Citations
- OREGON Lecture #6, pp. 199-200.
