Affiliation:
1. PhD Degree Program in Mathematics, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
2. Center of Excellence in Mathematics and Applied Mathematics, Department of Mathematics, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
Abstract
A Banach spaceXis said to have the fixed point property if for each nonexpansive mappingT:E→Eon a bounded closed convex subsetEofXhas a fixed point. LetXbe an infinite dimensional unital Abelian complex Banach algebra satisfying the following: (i) condition (A) in Fupinwong and Dhompongsa, 2010, (ii) ifx,y∈Xis such thatτx≤τy,for eachτ∈Ω(X),thenx≤y,and (iii)inf{r(x):x∈X,x=1}>0.We prove that there exists an elementx0inXsuch that〈x0〉R=∑i=1kαix0i:k∈N,αi∈R¯does not have the fixed point property. Moreover, as a consequence of the proof, we have that, for each elementx0inXwith infinite spectrum andσ(x0)⊂R,the Banach algebra〈x0〉=∑i=1kαix0i:k∈N,αi∈C¯generated byx0does not have the fixed point property.