Math trick reverses spirals, providing new ways to explore materials
Physicists have put a new twist on the humble corkscrew. Just as a butterfly appears identical to its mirror image, objects made of structures that tilt, twist or spiral possess a symmetry now recognized for the first time.
The new discovery is based on a mathematical operation that transforms a clockwise helix into a counterclockwise one, or vice versa.
“Normally, a helix flips when you put a mirror up to it,” says Venkatraman Gopalan, a materials scientist at Pennsylvania State University in University Park. “We’ve developed a special kind of mirror with thi