The Quarterly Journal of Mathematics Advance Access published online on January 31, 2008
The Quarterly Journal of Mathematics, doi:10.1093/qmath/ham054
POLYNOMIAL NUMERICAL INDEX FOR SOME COMPLEX VECTOR-VALUED FUNCTION SPACES

Department of Mathematics, POSTECH, Pohang 790-784, South Korea


Departamento de Análisis Matemático, Universidad de Valencia, Doctor Moliner 50, 46100 Burjasot, Valencia, Spain
Departamento de Análisis Matemático, Facultad de Ciencias, Universidad de Granada, 18071 Granada, Spain
¶ Corresponding author. E-mail: mmartins{at}ugr.es
Received 20 April 2007;
revised 5 November 2007
| Abstract |
|---|
We study the relation between the polynomial numerical indices of a complex vector-valued function space and the ones of its range space. It is proved that the spaces C(K, X) and L
(µ, X) have the same polynomial numerical index as the complex Banach space X for every compact Hausdorff space K and every
-finite measure µ, which does not hold any more in the real case. We give an example of a complex Banach space X such that, for every k
slant 2, the polynomial numerical index of order k of X is the greatest possible, namely 1, while the one of X** is the least possible, namely kk/(1–k). We also give new examples of Banach spaces with the polynomial Daugavet property, namely L
(µ, X) when µ is atomless, and Cw(K, X), Cw*(K, X*) when K is perfect.
E-mail: mathchoi{at}postech.ac.kr
E-mail: domingo.garcia{at}uv.es
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