Ai Weiwei. Dust to Dust, 2009 © Ai Weiwei. Photo: Ai Weiwei

Barry Le Va. Set I A placed B placed. Set II A dropped. B dropped. Set III A placed. B dropped. Set IV placed, 1968. Courtesy the artist and Sonnabend Gallery, New York. Photo: Douglas M Parker Studio

Mona Hatoum. Drowning Sorrows (wine bottles), 2004. Collezione Pier Luigi e Natalina Remotti. Courtesy Galleria Continua, San Gimignano/Beijing/Le Moulin. Photo: Ela Bialkowska

Claire Fontaine. Untitled (Feng-Shui Crystals), 2009. Installation at T293, Naples, February 12 – March 28, 2009. Courtesy T293, Naples/Rome. Photo: Danilo Donzelli © Claire Fontaine by SIAE 2013

Walead Beshty, 2008-2012. Courtesy the artist, Regen Projects, Los Angeles, and Thomas Dane Gallery, London