Essential commutant of analytic Toeplitz operators

摘要

LET B_n be the unit ball of C~n. The n-dimensional vector space over the complex field C, S_n - 9B_n is the boundary of B_n . We use a to denote the unique rotation-invariant probability measure on S_n . The Lebesgue spaces L_2( S_n, dσ) have their customary meaning. H~2 ( S_n ) denotes the Hardy space which is the subspace of L~2 (S_n, dσ). For φ∈L~∞ (Sn), T_φ and H_φ denotes the Toeplitz operator and the Hankel operator respectively.