We prove a conjecture of Yood regarding the nonexistence of submultiplicative norms on the algebra C(T) of all continuous functions on a topological space T which admits an unbounded continuous function. We also exhibit a quotient of C(T) which does not admit a nonzero positive linear functional. Finally, it is shown that the algebra L(X) of all linear operators on an infinite-dimensional vector space X admits no nonzero submultiplicative seminorm.
@article{bwmeta1.element.bwnjournal-article-smv116i3p299bwm, author = {Michael Meyer}, title = {Some algebras without submultiplicative norms or positive functionals}, journal = {Studia Mathematica}, volume = {113}, year = {1995}, pages = {299-302}, zbl = {0838.46041}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-smv116i3p299bwm} }
Meyer, Michael. Some algebras without submultiplicative norms or positive functionals. Studia Mathematica, Tome 113 (1995) pp. 299-302. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-smv116i3p299bwm/
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