how do you think of the gap between the rishest and the poor

The gap between rich and poor is getting bigger ,according to a.report released .Wealthy households are widening the gap with the poor,they are also leaving middle-income earners further behind,with potentially ominous consequences if the global financial crisis sparks a long recession.There is one question I have in mind namely,why are the rich getting richer and the poor getting poorer?From these questions and answer we might be able to resolve this issue.