不可能物体：数学家设计出新型悖论形状

Mathematicians have designed a new kind of paradoxical shape TEXT BY CLARA MOSKOWITZ GRAPHICS BY ROBERT GHRIST AN IMPOSSIBLE OBJECT is something that looks realistic when drawn but can’t exist in real life. Dutch artist M. C. Escher is famous for depicting, for instance, staircases and waterfalls that are impossible to build in three dimensions. Many of Escher’s works are based on constructions by British mathematicians Roger and Lionel Penrose, such as the Penrose triangle and Penrose stairs, which they published in the 1950s. Reutersvärd triangle Penrose triangle Penrose staircase Now mathematicians Robert Ghrist of the University of Pennsylvania and Zoe Cooperband of the U.S. Naval Research Laboratory have created a mathematical classification system for visual paradoxes. …