Mean oscillations and equimeasurable rearrangements of functions

Various applications of equimeasurable function rearrangements to the “best constant”-type problems are considered in this volume. Several classical theorems are presented along with some very recent results. In particular, the text includes a product-space extension of the Rising Sun lemma, a product-space version of the John-Nirenberg inequality for bounded mean oscillation (BMO) functions with sharp exponent, a refinement of the Gurov-Reshetnyak lemma, sharp embedding theorems for Muckenhoupt, Gurov-Reshetnyak, reverse H?lder, and Gehring classes, etc. This volume is interesting for graduate students and mathematicians involved with these topics.