Weak Hopf Algebra And Its Related Structures

It constructs a Morita context relating A#H and AH, where H is a semisimple weak Hopf algebra, A is a left H—module commutative algebra. Then it develops some important results on Hopf algebra for weak Hopf algebra. Then weak Galois extension is introduced and it gives a sufficient condition to infer weak Galois extension . At last, it quotes the definition of weak entwining structures, and studies the relation among the categories of the weak entwining modules.