## Arkiv för Matematik

• Ark. Mat.
• Volume 40, Number 2 (2002), 323-333.

### On M-structure, the asymptotic-norming property and locally uniformly rotund renormings

#### Abstract

Letr, s ∈ [0, 1], and let X be a Banach space satisfying the M(r, s)-inequality, that is, $\parallel x^{***} \parallel \geqslant r\parallel \pi _X x^{***} \parallel + s\parallel x^{***} - \pi _X x^{***} \parallel for x^{***} \in X^{***} ,$ where πX is the canonical projection from X*** onto X*. We show some examples of Banach spaces not containing c0, having the point of continuity property and satisfying the above inequality for r not necessarily equal to one. On the other hand, we prove that a Banach space X satisfying the above inequality for s=1 admits an equivalent locally uniformly rotund norm whose dual norm is also locally uniformly rotund. If, in addition, X satisfies $\mathop {\lim \sup }\limits_\alpha \parallel u^* + sx_\alpha ^* \parallel \leqslant \mathop {\lim \sup }\limits_\alpha \parallel v^* + x_\alpha ^* \parallel$ whenever u*, v*X* with ‖u*‖≤‖v*‖ and (x ${}_{α}^{*}$ ) is a bounded weak* null net in X*, then X can be renormed to satisfy the, M(r, 1) and the M(1, s)-inequality such that X* has the weak* asymptotic-norming property I with respect to BX.

#### Article information

Source
Ark. Mat., Volume 40, Number 2 (2002), 323-333.

Dates
Revised: 12 December 2001
First available in Project Euclid: 31 January 2017

https://projecteuclid.org/euclid.afm/1485898773

Digital Object Identifier
doi:10.1007/BF02384539

Mathematical Reviews number (MathSciNet)
MR1948068

Zentralblatt MATH identifier
1034.46010

Rights

#### Citation

Nieto, Eduardo; Rivas, Migdalia. On M -structure, the asymptotic-norming property and locally uniformly rotund renormings. Ark. Mat. 40 (2002), no. 2, 323--333. doi:10.1007/BF02384539. https://projecteuclid.org/euclid.afm/1485898773

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