On the frame of the unit ball of Banach spaces

• Autorzy: Ryotaro Tanaka
• Języki publikacji: EN

Abstrakty

EN

The notion of the frame of the unit ball of Banach spaces was introduced to construct a new calculation method for the Dunkl-Williams constant. In this paper, we characterize the frame of the unit ball by using k-extreme points and extreme points of the unit ball of two-dimensional subspaces. Furthermore, we show that the frame of the unit ball is always closed, and is connected if the dimension of the space is not less than three. As infinite dimensional examples, the frame of the unit balls of c 0 and ℓ p are determined.

Słowa kluczowe

EN

k-extreme point; Exposed face; Frame

Kategorie tematyczne

• 46B20: Geometry and structure of normed linear spaces

• Wydawca: De Gruyter Open
• Czasopismo: Open Mathematics
• Rocznik: 2014
• Tom: 12
• Numer: 11
• Strony: 1700-1713

Daty

wydano

2014-11-01

online

2014-06-29

Twórcy

autor

Ryotaro Tanaka

• Niigata University

Bibliografia

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Identyfikatory

DOI

10.2478/s11533-014-0437-7