Intriguing exhibition at Tate Modern of sculptures by Alexander Calder, the man who invented the modern mobile – and I’m not talking about telephones. His early wire portraits of friends such as Josephine Baker and Joan Miro are extraordinary for their technique as much as their revelatory qualities. But once his work had lifted off and ceased to be static thanks to either through breeze-power or an electric motor it moves on to a higher plane in every sense. Some of the later mobiles (a description coined, almost inevitably, by Duchamp) are quite simply out of this world. The show runs till April 3