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Does there exist an isometric automorphism of $c_0$ which is not a permutation of coordinates?

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    $\begingroup$ I assume you forgot to add "followed by multiplication by a sequence $(a_n)$ with $|a_n|=1$ for all $n$" at the end of your sentence. It is rather elementary that these are all there are. Either prove it directly or take the adjoint of the isometry and use the characterization of isometries of $L_1$ spaces that can be read in many books, including Royden's Real Analysis, Chpt. 15, section 7. $\endgroup$
    – Bill Johnson
    Commented Oct 18, 2012 at 18:24
  • $\begingroup$ Indeed, I was looking for "non trivial" ones. Thanks a lot for the answer. $\endgroup$
    – robibok
    Commented Oct 18, 2012 at 20:33

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