In a groundbreaking advance that challenges fundamental assumptions in material science, researchers from AMOLF and ARCNL have engineered structures capable of performing what they term “countersnapping” — a mechanical phenomenon wherein materials, when pulled outward, defy intuition by snapping inward, contracting suddenly rather than stretching. This counterintuitive response, now experimentally demonstrated for the first time, signals a paradigm shift in how we understand and harness mechanical instabilities.

When you pull something—like a rubber band—you expect it to get longer. But what if it did the opposite? What if it suddenly shrank instead?

Proceedings of the National Academy of Sciences (PNAS), a peer reviewed journal of the National Academy of Sciences (NAS) - an authoritative source of high-impact, original research that broadly spans...

Proceedings of the National Academy of Sciences, Volume 122, Issue 16, April 2025. SignificanceFrom an umbrella flipping inside out during a gust of wind to a slender stick bowing when compressed, mechanical instabilities are often seen as undesirable. However, they can also be leveraged, as illustrated by the snapping-based prey ...