Derivations decreasing the spectral radius (Q689652)

From MaRDI portal





scientific article; zbMATH DE number 446280
Language Label Description Also known as
English
Derivations decreasing the spectral radius
scientific article; zbMATH DE number 446280

    Statements

    Derivations decreasing the spectral radius (English)
    0 references
    0 references
    15 November 1993
    0 references
    The following theorem is proved: Let \(A\) be a unital Banach algebra and let \(d\) be an inner derivation of \(A\). Suppose that for some positive number \(M\) and for all \(x\in A\) the inequality \(r(d(x))\leq Mr(x)\) holds. Then \(d\) maps \(A\) into \(\text{rad}(A)\).
    0 references
    unital Banach algebra
    0 references
    inner derivation
    0 references

    Identifiers