Gisin'S Theorem Via Hardy'S Inequality

The original gisin's theorem states that all the entangled pure states of two qubits violate a single bell's inequality,namely clause-horne-shimony-holt (chsh) inequality. in this paper we show that all the entangled pure states for n particles also violate a single bell's inequality,namely hardy's inequality arising from hardy's nonlocality test without inequality. thus gisin's theorem is proved in its most general form from which it follows that for pure states bell's nonlocality and quantum entanglement are equivalent. in the sense of gisin's theorem,hardy's inequality can be regarded as a natural generalization of chsh inequality.