Characterization of a rearrangement-invariant hull of a Besov space via interpolation

Abstract

The K-functional for the pair consisting of a Sobolev-type space and a rearrangement-invariant space is calculated. This result is used to estimate rearrangements of functions by moduli of continuity.

The rearrangement-invariant hull of a Besov space is characterized.

Keywords

• Besov spaces
• Lorentz spaces
• interpolation
• K-functionals
• rearrangement-invariant spaces
• rearrangement-invariant hull