Acta mathematica scientia,Series A ›› 2010, Vol. 30 ›› Issue (1): 179-196.

• Articles • Previous Articles     Next Articles

Cohomology for Coalgebras with Twisted Coactions of Commutative Hopf Algebras

JU Teng-Xia   

  1. Faculty of Science, Nantong University, Jiangsu Nantong  226007
  • Received:2008-05-08 Revised:2009-09-09 Online:2010-01-01 Published:2010-01-01
  • Supported by:

    国家自然科学基金(10771182)资助.

Abstract:

In this paper, we show that the twisted coactions of commutative Hopf algebras H on coalgebras C are invertible if the corresponding coassociators are convolution invertible. In this case, we define the regular cohomology and show that every invertible twisted coaction gives rise to a regular cohomology class of H with coefficients in C of degree three. We also show that the obstruction for $\rho$ vanishes if and only if the the twisted coaction ρ is corresponding to a cleft coextension.

Key words: Sweedler cohomology, Regular cohomology, Twisted coaction, Cleft coextension

CLC Number: 

  • 16W30
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