A note on the essential norm of composition operators from H ^p(B _N) to H ^q(B _N)

Abstract

The authors give an upper bound of the essential norms of composition operators between Hardy spaces of the unit ball in terms of the counting function in the higher dimensional value distribution theory defined by Professor S. S. Chern. The sufficient condition for such operators to be bounded or compact is also given.

Keywords

Essential norm / Composition operator / Hardy space

References

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