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Existence of Fixed Points of Nonexpansive Mappings in Uniformly n-Convex n-Banach Spaces
Subject area: Science,Engineering and Technology · Area of research: Pure Mathematics
Abstract
This paper establishes the existence of fixed points of nonexpansive mappings on bounded closed convex subsets of uniformly n-convex n-Banach spaces. Building on the geometric properties of such spaces—reflexivity, weak compactness of bounded closed convex sets, and n-normal structure—we first prove an n-demi-closedness principle: for a nonexpansive self-map T, the mapping I-T is demi-closed at zero. Using this principle together with an approximate fixed point sequence generated by a family of n-normed contractions, we prove an n-normed analogue of the Browder–Göhde–Kirk theorem, namely that every nonexpansive self-map of a nonempty bounded closed convex subset of a uniformly n-convex n-Banach space has a fixed point. We further show that the fixed point set is closed and convex, and we establish a fixed point theorem valid in any reflexive n-Banach space with n-normal structure, obtained through a minimal-invariant-set argument of Kirk type. The results extend the classical fixed point theory of nonexpansive mappings, and the case n=2, to all n≥2.
Keywords
Approximate fixed point sequence, Demi-closedness, Fixed point property, Nonexpansive mapping, n-Normal structure.
References
[1] S. Gähler, “Lineare 2-normierte Räume,” Math. Nachr., vol. 28, pp. 1–43, 1965.
[2] Misiak, “n-inner product spaces,” Math. Nachr., vol. 140, pp. 299–319, 1989. Wiley
[3] H. Gunawan and M. Mashadi, “On n-normed spaces,” Int. J. Math. Math. Sci., vol. 27, no. 10, pp. 631–639, 2001. Wiley
[4] H. Gunawan, E. Kikianty, and M. Mashadi, “On n-inner product, n-norms, and the Cauchy–Schwarz inequality,” Sci. Math. Jpn., vol. 5, pp. 47–54, 2005.
[5] J. A. Clarkson, “Uniformly convex spaces,” Trans. Amer. Math. Soc., vol. 40, no. 3, pp. 396–414, 1936. American Mathematical Society
[6] F. E. Browder, “Fixed-point theorems for noncompact mappings in Hilbert space,” Proc. Nat. Acad. Sci. U.S.A., vol. 53, pp. 1272–1276, 1965. PubMed
[7] D. Göhde, “Zum Prinzip der kontraktiven Abbildung,” Math. Nachr., vol. 30, pp. 251–258, 1965. Wiley
[8] W. A. Kirk, “A fixed point theorem for mappings which do not increase distances,” Amer. Math. Monthly, vol. 72, no. 9, pp. 1004–1006, 1965. JSTOR
[9] D. P. Milman, “On some criteria for the regularity of spaces of the type B,” Dokl. Akad. Nauk SSSR, vol. 20, pp. 243–246, 1938.
[10] J. Pettis, “A proof that every uniformly convex space is reflexive,” Duke Math. J., vol. 5, no. 2, pp. 249–253, 1939.
[11] Z. Opial, “Weak convergence of the sequence of successive approximations for nonexpansive mappings,” Bull. Amer. Math. Soc., vol. 73, pp. 591–597, 1967. American Mathematical Society
[12] W. F. Eberlein, “Weak compactness in Banach spaces,” Proc. Nat. Acad. Sci. U.S.A., vol. 33, pp. 51–53, 1947. PubMed
[13] Z. Lewandowska, “Banach–Steinhaus theorems for 2-normed spaces,” Bull. Korean Math. Soc., vol. 38, no. 2, pp. 325–341, 2001.
[14] Y. J. Cho, K. S. Ha, and S. S. Kim, “Fixed point theorems for nonexpansive mappings in 2-normed spaces,” J. Appl. Math. Comput., vol. 26, pp. 207–216, 2008.
How to cite this paper
@article{1723338,
author = {Anyande Benard Alex, Patrick Makila Wanjala},
title = {Existence of Fixed Points of Nonexpansive Mappings in Uniformly n-Convex n-Banach Spaces},
journal = {Iconic Research And Engineering Journals},
year = {2026},
volume = {10},
number = {3},
pages = {2494-2497},
issn = {2456-8880},
url = {https://www.irejournals.com/formatedpaper/1723338.pdf},
abstract = {This paper establishes the existence of fixed points of nonexpansive mappings on bounded closed convex subsets of uniformly n-convex n-Banach spaces. Building on the geometric properties of such spaces—reflexivity, weak compactness of bounded closed convex sets, and n-normal structure—we first prove an n-demi-closedness principle: for a nonexpansive self-map T, the mapping I-T is demi-closed at zero. Using this principle together with an approximate fixed point sequence generated by a family of n-normed contractions, we prove an n-normed analogue of the Browder–Göhde–Kirk theorem, namely that every nonexpansive self-map of a nonempty bounded closed convex subset of a uniformly n-convex n-Banach space has a fixed point. We further show that the fixed point set is closed and convex, and we establish a fixed point theorem valid in any reflexive n-Banach space with n-normal structure, obtained through a minimal-invariant-set argument of Kirk type. The results extend the classical fixed point theory of nonexpansive mappings, and the case n=2, to all n≥2.},
keywords = {Approximate fixed point sequence, Demi-closedness, Fixed point property, Nonexpansive mapping, n-Normal structure.},
month = {September},
}