# Rachel Greenfeld

### ‘Nasty’ Geometry Breaks Decades-Old Tiling Conjecture

"'It’s easy to cover a floor with copies of squares, triangles or hexagons [...] but only in ways that never repeat. 'You want to understand the structure of such tilings,' said Rachel Greenfeld, a mathematician at the Institute for Advanced Study in Princeton, New Jersey. 'How crazy can they get?' Pretty crazy, it turns out."