| Medieval Islamic artists beat Western scientists by 500 years in discovery |
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23 February 2007, for Nature Network Boston The intricate patterns of tiles on the walls of ancient mosques and shrines reveal that Islamic artists of the Middle Ages created a complex class of structures called quasicrystals, which Western physicists discovered some 500 years later, according to a paper in this week’s Science.
Darb-i Imam shrine in Isfahan, Iran (Image courtesy of K. Dudley and M. Elliff) In regular crystals like diamonds, all the atoms fit together in a regular, repeating pattern. But in quasicrystals, the pattern never repeats itself exactly. Before physicists discovered quasicrystals, famed U.K. mathematician Roger Penrose proved their existence mathematically in the 1970s, using sets of tiles covering a surface. Now two physicists say that Islamic artists working with tiles may have discovered quasicrystal structures in the Middle Ages. Peter Lu at Harvard University became intrigued by the patterns of tiling, called girih, on a mosque while visiting Uzbekistan. By analyzing a few thousand photographs of tiling on various buildings from Turkey to Afghanistan, Lu and Peter Steinhardt of Princeton University found that the patterns of tiles displayed telltale signs of quasicrystals, such as pentagons and 10-pointed stars. They also found that one shrine in Iran had a true quasicrystal pattern on it. The physicists examined scrolls on which medieval Islamic artists sketched their designs and found that they were using a tiling pattern similar to Penrose’s to create the complex patterns. Still, they say it’s not clear how well the artists understood the underlying structures. |
