Boundedness of pseudo-differential operators in subelliptic Sobolev and Besov spaces on compact Lie groups

Abstract: In this paper we investigate the Besov spaces on compact Lie groups in a subelliptic setting, that is, associated with a family of vector fields, satisfying the H\"ormander condition, and their corresponding sub-Laplacian. Embedding properties between subelliptic Besov spaces and Besov spaces associated to the Laplacian on the group are proved. We link the description of subelliptic Sobolev spaces with the matrix-valued quantisation procedure of pseudo-differential operators in order to provide subelliptic Sobolev and Besov estimates for operators in the H\"ormander classes. Interpolation properties between Besov spaces and Triebel-Lizorkin spaces are also investigated.