On w-Isbell-convexity

Olivier Olela Otafudu

https://orcid.org/0000-0001-9593-7899

South Africa

North-West University

School of Mathematical and Statistical Sciences

Katlego Sebogodi

South Africa

University of Johannesburg

Department of Mathematics and Applied Mathematics

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Accepted: 2021-12-10

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Published: 2022-04-01

DOI: https://doi.org/10.4995/agt.2022.15739
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Keywords:

Modular pseudometric, Isbell-convexity, $w$-Isbell-convexity

Supporting agencies:

This research was not funded

Abstract:

Chistyakov introduced and developed a concept of modular metric for an arbitrary set in order to generalise the classical notion of modular on a linear space. In this article, we introduce the theory of hyperconvexity in the setting of modular pseudometric that is herein called w-Isbell-convexity. We show that on a modular set, w-Isbell-convexity is equivalent to hyperconvexity whenever the modular pseudometric is continuous from the right on the set of positive numbers.

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References:

A. A. N. Abdou, Fixed points of Kannan maps in modular metric spaces, AIMS Maths 5 (2020), 6395-6403. https://doi.org/10.3934/math.2020411

A. A. N. Abdou and M. A. Khamsi, Fixed point results of pointwise contractions in modular metric spaces, Fixed Point Theory Appl. 2013 (2013):163. https://doi.org/10.1186/1687-1812-2013-163

C. Alaca, M. E. Ege and C. Park, Fixed point results for modular ultrametric spaces, J. Comput. Anal. Appl. 20 (2016), 1259-1267.

A. H. Ansari, M. Demma, L. Guran, J. R. Lee and C. Park, Fixed point results for C-class functions in modular metric spaces. J. Fixed Point Theory Appl. 20, no. 3 (2018), Paper No. 103. https://doi.org/10.1007/s11784-018-0580-z

V. V. Chistyakov, A fixed point theorem for contractions in modular metric spaces, arXiv:1112.5561.

V. V. Chistyakov, Metric modular spaces: Theory and applications, SpringerBriefs in Mathematics, Springer, Switzerland, 2015. https://doi.org/10.1007/978-3-319-25283-4

V. V. Chistyakov, Modular metric spaces generated by F-modulars, Folia Math. 15 (2008), 3-24.

V. V. Chistyakov, Modular metric spaces, I: Basic concepts, Nonlinear Anal. 72 (2010), 1-14. https://doi.org/10.1016/j.na.2009.04.057

S. Cobzas, Functional Analysis in Asymmetric Normed Spaces, Frontiers in Mathematics, Springer, Basel, 2012. https://doi.org/10.1007/978-3-0348-0478-3

M. E. Ege and C. Alaca, Fixed point results and an application to homotopy in modular metric spaces, J. Nonlinear Sci. Appl. 8 (2015), 900-908. https://doi.org/10.22436/jnsa.008.06.01

M. E. Ege and C. Alaca, Some properties of modular S-metric spaces and its fixed point results, J. Comput. Anal. Appl. 20 (2016), 24-33.

M. E. Ege and C. Alaca, Some results for modular b-metric spaces and an application to system of linear equations, Azerb. J. Math. 8 (2018), 3-14.

R. Espínola and M. A. Khamsi, Introduction to hyperconvex spaces, in: Handbook of Metric Fixed Point Theory, Kluwer Academic, Dordrecht, The Netherlands (2001), pp. 39135. https://doi.org/10.1007/978-94-017-1748-9_13

A. Gholidahneh, S. Sedghi, O. Ege, Z. D. Mitrovic and M. de la Sen, The Meir-Keeler type contractions in extended modular b-metric spaces with an application, AIMS Math. 6 (2021), 1781-1799. https://doi.org/10.3934/math.2021107

H. Hosseinzadeh and V. Parvaneh, Meir-Keeler type contractive mappings in modular and partial modular metric spaces, Asian-Eur. J. Math. 13 (2020): 2050087. https://doi.org/10.1142/S1793557120500874

E. Kemajou, H.-P. Künzi and O. Olela Otafudu, The Isbell-hull of di-space, Topology Appl. 159 (2012), 2463-2475. https://doi.org/10.1016/j.topol.2011.02.016

M. A. Khamsi and W. A. Kirk, An Introduction to Metric Spaces and Fixed Point Theory, Pure and Applied Mathematics, Wiley-Interscience, New York, NY, USA, 2001. https://doi.org/10.1002/9781118033074

H.-P. Künzi, An introduction to quasi-uniform spaces, Contemp. Math. 486 (2009), 239-304. https://doi.org/10.1090/conm/486/09511

H.-P. Künzi and O. Olela Otafudu, q-hyperconvexity in quasipseudometric spaces and fixed point theorems, J. Funct. Spaces Appl. 2012 (2012): Art. ID 765903. https://doi.org/10.1155/2012/765903

N. Kumar and R. Chugh, Convergence and stability results for new three step iteration process in modular spaces, Aust. J. Math. Anal. Appl. 14 (2017): 14.

Y. Mutemwa, O. Olela Otafudu and H. Sabao, On gluing of quasi-pseudometric spaces, Khayyam J. Math. 6 (2020), 129-140.

O. Olela Otafudu, On one-local retract in quasi-metric spaces, Topology Proc. 45 (2015), 271-281.

O. Olela Otafudu and H. Sabao, Set-valued contractions and $q$-hyperconvex spaces, J. Nonlinear Convex Anal. 18 (2017), 1609-1617. https://doi.org/10.4995/agt.2017.5818

R. C. Sine, On nonlinear contraction semigroups in sup norm spaces, Nonlinear Anal. 3 (1979), 885-890. https://doi.org/10.1016/0362-546X(79)90055-5

H. Sabao and O. Olela Otafudu, On soft quasi-pseudometric spaces, Appl. Gen. Topol. 22 (2021), 17-30. https://doi.org/10.4995/agt.2021.13084

S. Salbany, Injective objects and morphisms, in: Categorical Topology and Its Relation to Analysis, Algebra and Combinatorics, Prague, 1988, World Sci. Publ., Teaneck, NJ, 1989, pp. 394-409.

S. Yamamuro, On conjugate space of Nakano space, Trans. Amer. Math. Soc. 90 (1959), 291-311. https://doi.org/10.1090/S0002-9947-1959-0132378-1

C. I. Zhu, J. Chen, X. J. Huang and J. H. Chen, Fixed point theorems in modular spaces with simulation functions and altering distance functions with applications, J. Nonlinear Convex Anal. 21 (2020), 1403-1424.

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