Rational Expectation Can Preclude Trades

We consider a pure exchange economy under uncertainty in which the traders have the non-partition structure of information. They willing to trade the amounts of state-contingent commodities and they know their own expectations. Common knowledge of these conditions among all the traders can preclude trade if the initial endowments allocation is ex-ante Pareto optimal. Furthermore we introduce rational expectations equilibrium under the non-partition information, and prove the existence theorem and the fundamental theorems of welfare economics.