We characterize the functions f for which the superposition operator T-f (g) := f o g acts in the Holder-Zygmund spaces B-infinity,infinity(s) (R-n) and in the spaces BMO(R-n), VMO(R-n), CMO(R-n). Further we study the continuity and the differentiability of T-f in those various function spaces.
机构:
Wuhan Univ, Sch Math & Stat, Wuhan 430072, Peoples R China
Wuhan Inst Technol, Sch Sci, Wuhan 430074, Peoples R ChinaWuhan Univ, Sch Math & Stat, Wuhan 430072, Peoples R China
机构:
St.Petersburg Department of V. A. Steklov Mathematical Institute, St.PetersburgSt.Petersburg Department of V. A. Steklov Mathematical Institute, St.Petersburg