Resumen de A characterization of BMO self-maps of a metric measure space

Juha Kinnunen , Riikka Korte, Niko Marola, Nageswari Shanmugalingam

• This paper studies functions of bounded mean oscillation ( BMO ) on metric spaces equipped with a doubling measure. The main result gives characterizations for mappings that preserve BMO . This extends the corresponding Euclidean results by Gotoh to metric measure spaces. The argument is based on a generalization Uchiyama’s construction of certain extremal BMO -functions and John-Nirenberg’s lemma.