On the Hochschild cohomology for Frobenius kernels

In this paper the authors investigate the structure of the Hochschild cohomology for Frobenius kernels. The authors first establish some fundamental constructions to compute Hochschild cohomology by using spectral sequences. This enables the authors to provide a complete description of the G G -algebra structure of the Hochschild cohomology for the first Frobenius kernel G 1 G₁ where G = S L 2 G=SL₂ . This computation heavily relies on the calculation of the adjoint action on the restricted enveloping algebra.