Voices are raised around the world about the risks to the global economy if the U.S. does not act to raise its debt ceiling and causes a default on its sovereign debt.Global Economy,China,International Monetary Fund,Japan,Lehman Brothers,Olivier Blanchard,Rodrigo Vergara,Swiss National Bank,Switzerland,Taro Aso,U.S. Congress,United States,United States debt-ceiling crisis,Alex Erquicia