Latest documents http://publikationen.stub.uni-frankfurt.de/index/index/ Thu, 07 Apr 2005 08:23:03 +0200 Thu, 07 Apr 2005 08:23:03 +0200 http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/4283 We show that P(n)*(P(n)) for p = 2 with its geometrically induced structure maps is not an Hopf algebroid because neither the augmentation Epsilon nor the coproduct Delta are multiplicative. As a consequence the algebra structure of P(n)*(P(n)) is slightly different from what was supposed to be the case. We give formulas for Epsilon(xy) and Delta(xy) and show that the inversion of the formal group of P(n) is induced by an antimultiplicative involution Xi : P(n) -> P(n). Some consequences for multiplicative and antimultiplicative automorphisms of K(n) for p = 2 are also discussed. Christian Nassau article http://publikationen.stub.uni-frankfurt.de/frontdoor/index/index/docId/4283 Mon, 04 Jul 2005 08:23:03 +0200