Compactness of Embeddings
نویسنده
چکیده
An improvement of the author’s result, proved in 1961, concerning necessary and sufficient conditions for the compactness of embedding operators is given. A discussion of the necessity of the compatibility of the norms of the Banach spaces X2 and X3, where X2 ⊂ X3, is given. The injectivity of the embedding operator J : X2 → X3 implies this compatibility.
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