The compact Hankel operators form an 𝑀-ideal in the space of Hankel operators

The compact Hankel operators form an $M$-ideal in the space of Hankel operators
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by Daniel H. Luecking PDF

Proc. Amer. Math. Soc. 79 (1980), 222-224 Request permission

The theorem in the title is proved and used to give a new proof that elements of ${L^\infty }$ have best approximations in ${H^\infty } + C$.

References

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