Ben Bernanke, Jean Claude Trichet and other leading central bankers gather on Thursday in a lodge in the heart of Wyoming's Grand Teton national park for the Federal Reserve's annual Jackson Hole symposium.

In normal times it is a chance for central bankers to escape the day-to-day demands of macroeconomic management, listen to new academic research and get to know each other in a series of seminars, dinners and hikes beside lakes and through the nearby canyons.