Meromorphic functions with shared limit values.
A systematic investigation of algebras of holomorphic functions endowed with the Hadamard product is given. For example we show that the set of all non-invertible elements is dense and that each multiplicative functional is continuous, answering some questions in the literature.
Let be the set of all holomorphic functions on the domain Two domains and are called Hadamard-isomorphic if and are isomorphic algebras with respect to the Hadamard product. Our main result states that two admissible domains are Hadamard-isomorphic if and only if they are equal.
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