Approximation of functions and multifunctions by simple functions and multifunctions plays an important role in the theory separable valued functions and multifunctions. Also in case of Pettis integrable functions with values in non-separable Banach spaces there exists a satisfactory approximation theory, but in case of Pettis integrable multifunctions with values in non-separable Banach spaces no such a theory exists. It is the aim of this paper to fill in that gap.

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Kazimierz Musiał

Institute of Mathematics, University of Wrocław, Pl. Grunwaldzki 2/4, 50-384 Wrocław, Poland

musial@math.uni.wroc.pl
  1. M. Balcerzak, K. Musiał: Vitali type convergence theorems for Banach space valued integrable functions, Acta Math. Sin., Engl. Ser., to appear.Google Scholar
  2. R. G. Bartle, N. Dunford, J. Schwartz: Weak compactness and vector measures, Can. J. Math. 7 (1955) 289–305.https://doi.org/10.4153/CJM-1955-032-1Google Scholar
  3. B. Cascales, J. Rodríguez: Birkhoff integral for multi-valued functions, J. Math. Anal. Appl. 297 (2004) 540–560.https://doi.org/10.1016/j.jmaa.2004.03.026Google Scholar
  4. B. Cascales, V. Kadets, J. Rodríguez: Measurable selectors and set-valued Pettis integral in non-separable Banach spaces, J. Funct. Anal. 256(3) (2009) 673–699.https://doi.org/10.1016/j.jfa.2008.10.022Google Scholar
  5. C. Cascales, V. Kadets, J. Rodríguez: The Gelfand integral for multi-valued functions, J. Convex Analysis 18 (2011) 873–895.https://doi.org/10.68381/jca18055Google Scholar
  6. C. Castaing, A. Touzani, M. Valadier: Théorème de Hoffmann-Jørgensen et application aux amarts multivoques, Ann. Mat. Pura Appl., IV. Ser. 146 (1987) 383–397.https://doi.org/10.1007/BF01762371Google Scholar
  7. C. Castaing, M. Valadier: Convex Analysis and Measurable Multifunctions, Lecture Notes in Math. 580, Springer, Berlin (1977).https://doi.org/10.1007/BFb0087685Google Scholar
  8. A. Costé: Set-valued measures, in: Topology and Measure I (Zinnowitz, 1974), J. Flachsmeyer et al. (ed.), Wiss. Beiträge, Ernst-Moritz-Arndt-Universität, Greifswald (1978) 55–74.Google Scholar
  9. A. Costé: La propriété de Radon-Nikodým en intégration multivoque, C. R. Acad. Sci., Paris, Sér. A 280 (1995) 1515–1518.Google Scholar
  10. A. Costé, R. Pallu de la Berriére: Radon-Nikodým theorems for set-valued measures whose values are convex and closed, Ann. Soc. Math. Pol., Ser. I, Commentat. Math. (1978) 283–309.Google Scholar
  11. J. Diestel, J. J. Uhl: Vector Measures, Math. Surveys 15, Amer. Math. Soc., Providence (1977).https://doi.org/10.1090/surv/015Google Scholar
  12. J. Diestel: Sequences and Series in a Banach Space, Graduate Texts in Math. 92, Springer, Berlin (1984).https://doi.org/10.1007/978-1-4612-5200-9Google Scholar
  13. L. Di Piazza, K. Musiał: Set-Valued Kurzweil-Henstock-Pettis integral, Set-Valued Anal. 13 (2005) 167–179.https://doi.org/10.1007/s11228-004-0934-0Google Scholar
  14. K. El Amri, C. Hess: On the Pettis integral of closed valued multifunctions, Set-Valued Anal. 8 (2000) 329–360.https://doi.org/10.1023/A:1026547222209Google Scholar
  15. D. H. Fremlin, M. Talagrand: A decomposition theorem for additive set-functions with applications to Pettis integrals and ergodic means, Math. Z. 168 (1979) 117–142.https://doi.org/10.1007/BF01214191Google Scholar
  16. J. L. Gámez, J. Mendoza: On Denjoy-Dunford and Denjoy-Pettis integrals, Stud. Math. 130 (1998) 115–133.Google Scholar
  17. J. Hoffmann-Jørgensen: The law of large numbers for non-measurable and non-separable random elements, Astérisque 131 (1985) 299–356.Google Scholar
  18. L. Hörmander: Sur la fonction d’appui des ensembles convexes dans un espace localement convexe, Ark. Mat. 3 (1955) 181–186.https://doi.org/10.1007/BF02589354Google Scholar
  19. S. Hu, N. S. Papageorgiou: Handbook of Multivalued Analysis. Volume I: Theory, Kluwer, Dordrecht (1997).https://doi.org/10.1007/978-1-4615-6359-4Google Scholar
  20. M. Métivier: On strong measurability of Banach valued functions, Proc. Amer. Math. Soc. 21 (1969) 747–748.https://doi.org/10.2307/2036461Google Scholar
  21. K. Musiał: The weak Radon-Nikodým property in Banach spaces, Stud. Math. 64 (1979) 151–174.https://doi.org/10.4064/sm-64-2-151-174Google Scholar
  22. K. Musiał: Martingales of Pettis integrable functions, in: Measure Theory (Oberwolfach, 1979), D. Kölzow (ed.), Lecture Notes in Math. 794, Springer, Berlin (1980) 324–339.https://doi.org/10.1007/BFb0088234Google Scholar
  23. K. Musiał: Pettis integration, Rend. Circ. Mat. Palermo, II. Ser. Suppl. 10 (1985) 133–142.Google Scholar
  24. K. Musiał: Topics in the theory of Pettis integration, Rend. Ist. Mat. Univ. Trieste 23 (1991) 177–262.Google Scholar
  25. K. Musiał: A few remarks concerning the strong law of large numbers for non-separable Banach space valued functions, Rend. Ist. Mat. Univ. Trieste 26 (1993) 221–242.Google Scholar
  26. K. Musiał: Pettis integral, in: Handbook of Measure Theory I, E. Pap (ed.), North-Holland, Amsterdam (2002) 532–586.Google Scholar
  27. K. Musiał: Pettis integrability of multifunctions with values in arbitrary Banach spaces, J. Convex Analysis 18 (2011) 769–810.https://doi.org/10.68381/jca18049Google Scholar
  28. W. Sierpiński: Sur une décomposition d’ensembles, Monatsh. Math. Phys. 35 (1928) 239–243.https://doi.org/10.1007/BF01707443Google Scholar
  29. Y. Sonntag, C. Zălinescu: Scalar Convergence of Convex Sets, J. Math. Anal. Appl. 164 (1992) 219–241.https://doi.org/10.1016/0022-247X(92)90154-6Google Scholar
  30. M. Talagrand: Pettis integral and measure theory, Mem. Amer. Math. Soc. 307 (1984), 224 p.https://doi.org/10.1090/memo/0307Google Scholar
  31. M. Talagrand: The Glivenko-Cantelli problem, Ann. Probab. 15 (1987) 837–870.https://doi.org/10.1214/aop/1176992069Google Scholar

K. Musiał. “Approximation of Pettis Integrable Multifunctions with Values in Arbitrary Banach Spaces.” Journal of Convex Analysis 20 (2013), No. 3, 833–870. https://doi.org/10.68381/jca20045