 Interest in Islamic geometric patterns is increasing in the West, both among craftsmen and artists including M. C. Escher in the twentieth century, and among mathematicians and physicists including Peter J. Lu and Paul Steinhardt who controversially claimed in 2007 that tilings at the Darb-e Imam shrine in Isfahan could generate quasi-periodic patterns like Penrose tilings.Islamic art mostly avoids figurative images to avoid becoming objects of worship.This aniconism in Islamic culture caused artists to explore non-figural art, and created a general aesthetic shift toward mathematically-based decoration.