The rise and fall of L-spaces
Yıl 2020,
Cilt: 4 Sayı: 3, 152 - 166, 31.08.2020
Sehie Park
Öz
For a quite long period, the so-called L-structure or L-spaces have been studied by some authors. They have several trivial misconceptions such as their L-spaces extend the well-known generalized convex (G-convex) spaces. In order to clarify this matter and others, we show that our KKM theory on abstract convex spaces improves typical results in L-spaces. Main topics in this paper are related to extensions of the Himmelberg fixed point theorem. Since such studies are beyond of L-spaces, we cordially claim that now is the proper time to give up the useless study on L-spaces and their variants FC-spaces.
Kaynakça
- [1] N. Altwaijry, S. Ounaies, S. Chebbi, Generalized convexity and applications to fixed points and equilibria, J. Fixed Point
Theory Appl. (2018):3 https://doi.org/10.1007/s11784-018-0517-6
- [2] A. Amini-Harandi, A.P. Farajzadeh, D. O’Regan and R.P. Agarwal, Fixed point theorems for condensing multimaps on
abstract convex spaces, Nonlinear Functional Anal. Appl. 14(1) (2009) 109–120.
- [3] H. Ben-El-Mechaiekh, Continuous approximations of multifunctions, fixed points and coincidences, in “Approximation and
Optimization in the Carribean Il, Proceedings of the Second International Conference on Approximation and Optimization
in the Carribean”, (Florenzano et a1. Eds.), pp.69–97, Peter Lang Verlag, Frankfurt, 1995.
- [4] H. Ben-El-Mechaiekh, S. Chebbi, M. Florenzano and J.V. Llinares, Fixed point theorem without convexity, Working Paper
97-22 Economics Series, 11 April 1997, Departamento de Economia Universidad Carlos ill de Madrid CaIle Madrid.
- [5] H. Ben-El-Mechaiekh, S. Chebbi, M. Florenzano and J.V. Llinares, Abstract convexity and fixed points, J. Math. Anal.
Appl. 222 (1998) 138–150.
- [6] G. L. Cain, Jr. and L. González, The Knaster-Kuratowski-Mazurkiewicz theorem and abstract convexities, J. Math. Anal.
Appl. 338 (2008) 563–571.
- [7] T.H. Chang and C.L. Yen, KKM properties and fixed point theorems, J. Math. Anal. Appl. 203 (1996) 224-235.
- [8] S. Chebbi, P. Gourdel and H. Hammami, A generalization of Fan’s matching theorem, J. Fixed Point Theory Appl. 9
(2011) 117–124. DOI 10.1007/s11784-010-0022-z
- [9] X.P. Ding, General variational inequalities and equilibrium problems in generalized convex spaces, Comp. Math. Appl. 38
(1999) 189–197.
- [10] X.P. Ding, Abstract convexity and generalizations of Himmelberg type fixed-point theorems, Comp. Math. Appl. 41 (2001)
497–504.
- [11] X.P. Ding, Generalized G-KKM theorems in generalized convex spaces and their applications, J. Math. Anal. Appl. 266
(2002) 21–37. doi:10.1006/jmaa.2000.7207
- [12] X.P. Ding, Generalized L-KKM Type Theorems in L-convex spaces with applications, Comp. Math. Appl. 43 (2002)
1249–1256.
- [13] X.P. Ding, Generalizations of Himmelberg type fixed point theorems in locally FC-spaces, J. Sichuan Normal Univ. (NS)
29(1) (2006) 1–6.
- [14] X.P. Ding, The generalized game and the system of generalized vector quasi-equilibrium problems in locally FC-uniform
spaces, Nonlinear Anal. 68 (2008) 1028–1036.
- [15] X.P. Ding, Equilibrium existence theorems for multi-leader-follower generalized multiobjective games in FC-spaces, J. Glob.
Optim. (2012) DOI 10.1007/s10898-011-9717-y
- [16] X.P. Ding, and J.Y. Park, Continuous selection theorem, coincidence theorem, and generalized equilibrium in L-convex
spaces, Comp. Math. Appl. 44 (2002) 95–103.
- [17] X.P. Ding, and J.Y. Park, Generalized vector equilibrium problems in generalized convex spaces, J. Opt.Th. Appl. 120(2)
(2004) 327–353.
- [18] X.P. Ding and F.Q. Xia, Equilibria of nonparacompact generalized games with L F c -majorized correspondences in G-convex
spaces, Nonlinear Anal. 56 (2004) 831–849.
- [19] X.P. Ding, J.C. Yao and L.J. Lin, Solutions of system of generalized vector quasi-equilibrium problems in locally G-convex
uniform spaces, J. Math. Anal. Appl. 298 (2004) 398–410.
- [20] M. Fakhar and J. Zafarani, Matching and fixed point theorems in L-convex spaces, Research Gate 2014.
- [21] C. Horvath, Contractibility and generalized convexity, J. Math. Anal. Appl. 156 (1991) 341–357.
- [22] L.J. Lin and Z.T. Yu, Fixed point theorems of KKM type maps, Nonlinear Anal., TMA, 38 (1999) 265–275.
- [23] J.V. Llinares, Agstract convexity, some relations and applications, Optimization 51(6) (2002) 797–818.
- [24] S. Park, Some coincidence theorems on acyclic multifunctions and applications to KKM theory, Fixed Point Theory and
Applications (K.-K. Tan, ed.), World Scientific Publ., River Edge, NJ, (1992) 248–277.
- [25] S. Park, Foundations of the KKM theory via coincidences of composites of admissible u.s.c. maps, J. Korean Math. Soc.
31 (1994) 493–519.
- [26] S. Park, Coincidence theorems for the better admissible multimaps and their applications, Nonlinear Anal., TMA 30 (1997)
4183–4191.
- [27] S. Park, Fixed points of the better admissible multimaps, Math. Sci. Research Hot-Line 9 (1997) 1–6.
- [28] S. Park, Another five episodes related to generalized convex spaces, Nonlinear Funct. Anal. Appl. 3 (1998) 1–12.
- [29] S. Park, Continuous selection theorems in generalized convex spaces, Numer. Funct. Anal. Optimiz. 20 (1999) 567–583.
- [30] S. Park, Fixed points of better admissible maps on generalized convex spaces, J. Korean Math. Soc. 37 (2000) 885–899.
- [31] S. Park, On generalizations of the KKM principle on abstract convex spaces, Nonlinear Anal. Forum 11 (2006) 67–77.
- [32] S. Park, A unified fixed point theory in generalized convex spaces, Acta Math. Sinica, English Series 23 (2007) 1509–1526.
- [33] S. Park, Comments on some abstract convex spaces and the KKM spaces, Nonlinear Anal. Forum 12(2) (2007) 125–139.
- [34] S. Park, Elements of the KKM theory on abstract convex spaces, J. Korean Math. Soc. 45(1) (2008) 1–27.
- [35] S. Park, Remarks on fixed points, maximal elements, and equilibria of economies in abstract convex spaces, Taiwan. J.
Math. 12(6) (2008) 1365–1383.
- [36] S. Park, Generalizations of the Himmelberg fixed point theorem, Fixed Point Theory and Its Applications (Proc. ICFPTA-
2007), 123–132, Yokohama Publ. 2008.
- [37] S. Park, Fixed point theory of multimaps in abstract convex uniform spaces, Nonlinear Anal. 71 (2009) 2468–2480.
- [38] S. Park, Generalized convex spaces, L-spaces, and FC-spaces, J. Global Optim. 45(2) (2009) 203–210.
- [39] S. Park, The KKM principle in abstract convex spaces: Equivalent formulations and applications, Nonlinear Anal. 73
(2010) 1028–1042.
- [40] S. Park, The rise and decline of generalized convex spaces, Nonlinear Anal. Forum 15 (2010) 1–12.
- [41] S. Park, Generalizations of the KKMF principle having coercing families, J. Nonlinear Anal. Optim. 4(2) (2013) 30–40.
- [42] S. Park, Comments on “Some remarks on Park’s abstract convex spaces”, Nonlinear Anal. Forum 20 (2015) 161–165.
- [43] S. Park, A history of the KKM Theory, J. Nat. Acad. Sci., ROK, Nat. Sci. Ser. 56(2) (2017) 1–51.
- [44] S. Park, On further examples of partial KKM spaces, J. Fixed Point Theory, 2019, 2019:10 (18 June, 2019) 1–18.
- [45] S. Park, Extending the realm of Horvath spaces, J. Nonlinear Convex Anal. 20(8) (2019) 1609–1621.
- [46] S. Park and H. Kim, Admissible classes of multifunctions on generalized convex spaces, Proc. Coll. Natur. Sci. SNU 18
(1993) 1–21.
- [47] S. Park and H. Kim, Coincidence theorems for admissible multifunctions on generalized convex spaces, J. Math. Anal.
Appl. 197 (1996) 173–187.
- [48] S. Park and H. Kim, Foundations of the KKM theory on generalized convex spaces, J. Math. Anal. Appl. 209 (1997)
551–571.
- [49] S. Park and W. Lee, A unified approach to generalized KKM maps in generalized convex spaces, J. Nonlinear Convex
Anal. 2 (2001) 157–166.
- [50] N. Shioji, Unified forms of fixed point theorems and minimax inequalities, J. Nonlinear Var. Anal. 3(2) (2019) 181–187.
- [51] X. Wu and F. Li, Approximate selection theorems in H-spaces with applications, J. Math. Anal. Appl. 231 (1999) 118–132