The polarisation constant for JB*-triples

In [2]. Harris showed that for any J*- alegbra, Z, the polarisation constant c(n, Z) satisfies... A norm estimate for a derivative of the generalised Moebius transformation on JB*-triples is presented in Corollary 3.6 of [4]. This estimate allows us to extend the result of Harris to the case of JB*-triples, whose open unit balls have the same rich holomorphic structure as those of J*algebras. The JB*-triples are, indeed, exactly those Banach spaces whose open unit balls have a transitive group of biholomorphic automorphisms.