COMPOSITION OPERATORS ON PLURIHARMONIC HARDY SPACES ON THE UNIT BIDISC
DOI:
https://doi.org/10.18173/2354-1059.2026-0016Keywords:
composition operators, Hardy spaces, analytic functions, pluriharmonic functionsAbstract
In this paper, we study composition operators induced by holomorphic maps Φ = (ϕ, ψ) : \(\mathbb{D}\)\(\rightarrow\)\(\mathbb{D}\)2 acting from the pluriharmonic Hardy space \(H_h^2(\mathbb{D}\)2) into \(H_h^2(\mathbb{D}\)2). Using a structural decomposition of pluriharmonic functions on the bidisc into holomorphic and anti-holomorphic parts, we reduce the underlying problem to estimates on classical holomorphic Hardy spaces. These results extend the corresponding holomorphic theory to the pluriharmonic Hardy setting on the bidisc.
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