%0 Journal Article %T The Deformation Complex For DG Hopf Algebras %A Ronald Umble %J Mathematics %D 2001 %I arXiv %X Let H be a differential graded Hopf algebra over a field k. This paper gives an explicit construction of a triple cochain complex that defines the Hochschild-Cartier cohomology of H. A certain truncation of this complex is the appropriate setting for deforming H as an H(q)-structure. The direct limit of all such truncations is the appropriate setting for deforming H as a strongly homotopy associative structure. Sign complications are systematically controlled. The connection between rational perturbation theory and the deformation theory of certain free commutative differential graded algebras is clarified. %U http://arxiv.org/abs/math/0106266v2