Towards the end of http://www.youtube.com/watch?v=IAgV-LKTiMI&feature=channel" video at 54:55, the professor defines the four possible states of two entagled electrons as follows: singlet |0,0> = |u,d> - |d,u> triplet |1,1> = |u,u> |1,0> = |u,d> + |d,u> |1,-1> = |d,d> where: |u,u>, |u,d>, |d,u>, |d,d> form the 4 dimensional basis in the space of the total spin of the two electrons. This doesn't seem to jive with the four bell states as defiend on wikipedia http://en.wikipedia.org/wiki/Bell_state" [Broken]. For example, the first triplet state of the total spin as defined above |1,1> is an eigenstate of the |u,u> state and doen't need to be superposed. However, every Bell State as defined by wikipedia is a superposition of two states. What am I missing? Also, which of the four Bell States is the singlet state?