A packed Festival Hall and a cheering, stamping, standing ovation – hardly the usual welcome for an evening of contemporary music. Sitting, wizened and waistcoat-clad, at the centre of the front row was the reason: Ravi Shankar. Framed by the mathematical minimalism of John Adams’ Shaker Loops and Philip Glass’s Violin Concerto No. 1, Shankar’s first-ever symphony was last night given its world premiere by the London Philharmonic Orchestra.