A Banach algebra A is said to be topologically nilpotent if $sup{∥x₁... ...x_n∥^{1/n}: x_i ∈ A, ∥x_i∥ ≤ 1 (1 ≤ i ≤ n)}$ tends to 0 as n → ∞. We continue the study of topologically nilpotent algebras which was started in [2]
Institute of Mathematics, Czechoslovak Academy of Sciences, Žitná 25, 115 67 Praha 1, Czechoslovakia
Bibliografia
[1] F. F. Bonsall and J. Duncan, Complete Normed Algebras, Springer, Berlin 1973.
[2] P. G. Dixon, Topologically nilpotent Banach algebras and factorization, Proc. Roy. Soc. Edinburgh Sect. A 119 (1991), 329-341.
[3] P. G. Dixon and G. A. Willis, Approximate identities in extensions of topologically nilpotent Banach algebras, Proc. Roy. Soc. Edinburgh Sect. A, to appear.
[4] S. Grabiner, The nilpotency of Banach nil algebras, Proc. Amer. Math. Soc. 21 (1969), 510.
[5] G. Higman, On a conjecture of Nagata, Proc. Cambridge Philos. Soc. 52 (1956), 1-4.