Cahit Arf Lecture 2007 by Hendrik Lenstra

Hendrik Lenstra Mathematisch Instituut, Universiteit Leiden, Postbus 9512, 2300 RA Leiden, The Netherlands

Escher and Droste effect

Date: September 25, 2007
at 15:40

METU Cultural and Conventional Center
Hall- B
Middle East Technical University
Ankara, Turkey

Supported by


In 1956, the Dutch graphic artist M.C. Escher made an unusual lithograph with the title "Print Gallery". It shows a young man viewing a print in an exhibition gallery. Amongst the buildings depicted on the print, he sees a paradoxically the very same gallery that he is standing in. A lot is known about the way in which Escher made his lithograph. It is nor nearly as well known that it contains a hidden "Droste effect", or infinite repetition; but this is brought to light by a mathematical analysis of the studies used by Escher. On the basis of this discovery, a team of mathematicians at Leiden produced a series of hallucinating computer animations. These show, among others, what happens inside the mysterious spot in the middle of the lithograph that Escher left blank.