Evolution of Impossible Objects (Invited Paper)

Author Kokichi Sugihara

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Author Details

Kokichi Sugihara
  • Meiji Institute for Advanced Study of Mathematical Sciences, Meiji University, 4-21-1 Nakano, Nakano-ku, Tokyo 164-8525, Japan, http://www.isc.meiji.ac.jp/~kokichis/

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Kokichi Sugihara. Evolution of Impossible Objects (Invited Paper). In 9th International Conference on Fun with Algorithms (FUN 2018). Leibniz International Proceedings in Informatics (LIPIcs), Volume 100, pp. 2:1-2:8, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2018)


Impossible objects - 3D objects that can create a visual effect that seems impossible - can be classified by generation based on the order in which they were discovered or produced. The first generation consists of objects whose appearance when observed from a certain viewpoint matches a picture of an impossible object. Many such objects can be created, as there are multiple 3D objects that will project the same two-dimensional picture, including shapes that the human vision system is unable to perceive. The gap between the mathematical and the psychological can also create other types of "impossible" visual effects. Impossible objects are here classified into seven groups.

Subject Classification

ACM Subject Classification
  • Applied computing → Computer-aided design
  • Ambiguous cylinder
  • anomalous picture
  • impossible motion
  • impossible object
  • optical illusion


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