KentuckyFC writes "The banking system is closely regulated and monitored by central banks and other government agencies. But it has become common practice for banks to get around this by doing business in ways that don't show up on conventional balance sheets. This so-called shadow banking system is thought to be huge, but nobody knows exactly how big. Now three econophysicists have discovered that the size distribution of the world's largest financial firms significantly differs from the size distribution of smaller ones or indeed non-financial firms. And they hypothesize that the difference is the result of the hidden transactions that make up the shadow banking system. By this new measure, the shadow banking system has grown dramatically since the financial crisis and was worth over $100 trillion in 2012, significantly more than had been thought and more even than the GDP of the entire planet. Nothing to worry about, then."