Some aspects of generalized Zbăganu and James constant in Banach spaces

• Autorzy: Liu Qi , Sarfraz Muhammad , Li Yongjin

Identyfikatory

DOI

10.1515/dema-2021-0033

• Języki publikacji: EN

Abstrakty

EN

We shall introduce a new geometric constant CZ(λ, μ, X) based on a generalization of the parallelogram law, which was proposed by Moslehian and Rassias. First, it is shown that, for a Banach space, CZ(λ, μ, X) is equal to 1 if and only if the norm is induced by an inner product. Next, a characterization of uniformly non-square is given, that is, X has the fixed point property. Also, a sufficient condition which implies weak normal structure is presented. Moreover, a generalized James constant J(λ, X) is also introduced. Finally, some basic properties of this new coefficient are presented.

Słowa kluczowe

EN

Banach spaces; geometric constants; weak normal structure; Euler-Lagrange identity

PL

przestrzenie Banacha; model Eulera-Lagrange'a

• Wydawca: De Gruyter
• Czasopismo: Demonstratio Mathematica
• Rocznik: 2021
• Tom: Vol. 54, nr 1
• Strony: 299--310
• Opis fizyczny: Bibliogr. 36 poz.

Twórcy

autor

Liu Qi

• Department of Mathematics, Sun Yat-sen University, Guangzhou, 510275, P. R. China

autor

Sarfraz Muhammad

• Department of Mathematics, Sun Yat-sen University, Guangzhou, 510275, P. R. China

autor

Li Yongjin

• Department of Mathematics, Sun Yat-sen University, Guangzhou, 510275, P. R. China

Bibliografia

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Uwagi

PL

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2021).