It's the day after Cambridge physicist Stephen Hawking's 70th birthday party and David Harding, the head of one of the most successful hedge funds in the world, is bubbling with talk of black holes. Given the financial crisis of the last few years, some might see that as an unwise topic of conversation for a hedge fund manager. But for Harding, a physicist, the geekier the better. The 50-year-old runs Winton Capital, one of a secretive but influential band of computer-driven hedge funds that bet tens of billions of dollars on the world's financial markets using algorithms - mathematical instructions to computers - ... (full story)