Composition of maximal operators on the endpoint Sobolev space
摘要
In this paper we study the endpoint Sobolev regularity for composition of maximal operators. We prove some endpoint Sobolev bounds and continuity for the composition of maximal operators. In addition, we also obtain some new endpoint Sobolev bounds and continuity for fractional maximal functions. The main new idea includes some applications of the weak (1, 1) bound of the Hardy–Littlewood maximal operator and two basic inequalities of a