The Economist;Megachange;The World in 2052

In 2050 there will be 9.3 billion people alive - compared with 7 billion today - and the number will still be rising. The population aged over sixty-five will have more than doubled, to more than 16 per cent; China's GDP will be 80 per cent more than America's; and the number of cars on India's roads will have increased by 3,880 per cent. And, in 2050 it should be clear whether we are alone in the universe. What other megachanges can we expect - and what will their impact be?