It is proved (independently of the result of Holmes [Fund. Math. 140 (1992)]) that the dual space of the uniform closure of the linear span of the maps x ↦ d(x,a) - d(x,b), where d is the metric of the Urysohn space of diameter r, is (isometrically if r = +∞) isomorphic to the space of equivalence classes of all real-valued Lipschitz maps on . The space of all signed (real-valued) Borel measures on is isometrically embedded in the dual space of and it is shown that the image of the embedding is a proper weak* dense subspace of . Some special properties of the space are established.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-sm192-2-1, author = {Piotr Niemiec}, title = {Canonical Banach function spaces generated by Urysohn universal spaces. Measures as Lipschitz maps}, journal = {Studia Mathematica}, volume = {192}, year = {2009}, pages = {97-110}, zbl = {1176.46031}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-sm192-2-1} }
Piotr Niemiec. Canonical Banach function spaces generated by Urysohn universal spaces. Measures as Lipschitz maps. Studia Mathematica, Tome 192 (2009) pp. 97-110. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-sm192-2-1/