We study various properties of Lipschitz continuous linear selectors on the family of all convex, nonempty and compact subsets of Rn\mathbb{R}^n. In particular, it is shown that if s is such a selector then the Lipschitz constant of s can be estimated from below by the norm of s(Bn)s(B^n), where BnB^n is the unit ball. A notion of a parametric representation of convex bodies is introduced and illustrated with examples.

Contact details are reproduced from the original publication and may be historical.

Krzysztof Przesławski

Instytut Matematyki, Politechnika Zielonogórska, ul. Podgórna 50, 65-246 Zielona Góra, Poland

  1. Z. Artstein: Extensions of Lipschitz selections and an application to differential inclusions, Nonlinear Anal. 16 (1991) 701-704.https://doi.org/10.1016/0362-546X(91)90176-2Google Scholar
  2. J. P. Aubin, A. Cellina: Differential Inclusions, Springer, Berlin, 1984.https://doi.org/10.1007/978-3-642-69512-4Google Scholar
  3. J. P. Aubin, H. Frankowska: Set-Valued Analysis, Birkhäuser, Boston, 1990.Google Scholar
  4. F. Deutsch, Wu Li, Sung-Ho Park: Characterizations of continuous and Lipschitz continuous selections for metric projections in normed linear spaces, J. Approx. Theory 58 (1989) 297-314.https://doi.org/10.1016/0021-9045(89)90031-2Google Scholar
  5. G. Dommisch: On the existence of Lipschitz-continuous and differentiable selections for multifunctions, Parametric optimization and related topics, (Proc. Int. Conf., Plauen, Thüringen, October 1985) Math. Res. 35, 60-73, Akademie-Verlag, Berlin, 1987.https://doi.org/10.1515/9783112720936-005Google Scholar
  6. E. Giné, M. G. Hahn: M-infinitely divisible random compact convex sets, In: Probability in Banach Spaces V, Lectures Notes in Math. 1153, Springer-Verlag, Berlin et al. (1985).https://doi.org/10.1007/BFb0074952Google Scholar
  7. M. Gromov: Convex sets and Kähler manifolds, In: Advances in Differential Geometry and Topology, ed. F. Tricerri, World Scientific, Singapore (1990) 1-38.https://doi.org/10.1142/9789814439381_0001Google Scholar
  8. K. Leichtweiss: Konvexe Mengen, VEB Deutscher Verlag der Wissenschaften, Berlin, 1980.Google Scholar
  9. O. V. Levchuk: The Steiner derivative of locally Lipschitz functions, (Russian) Optimizatsiya 29 (46) (1982) 56-65.Google Scholar
  10. J. Lindenstrauss: On nonlinear projections in Banach spaces, Michigan Math. J. 11 (1964) 263-287.https://doi.org/10.1307/mmj/1028999141Google Scholar
  11. J. Mattioli: Minkowski operations and vector spaces, Set-Valued Analysis 3 (1995) 33-50.https://doi.org/10.1007/BF01033640Google Scholar
  12. W. Meyer: Characterization of the Steiner point, Pacific J. Math. 35 (1970) 717-725.https://doi.org/10.2140/pjm.1970.35.717Google Scholar
  13. Cz. Olech: Lexicographical order, range of integrals and "bang-bang" principle, In: Mathematical Theory of Control, Academic Press, New York (1967) 35-45.Google Scholar
  14. E. D. Positsel'skii: Characterization of Steiner points, (Russian) Mat. Zametki 14 (1973) 243-247.Google Scholar
  15. M. H. Protter, H. F. Weinberger: Maximum Principles in Differential Equations, Prentice-Hall, Englewood Cliffs, N.J., 1967.Google Scholar
  16. K. Przestawski, D. Yost: Lipschitz retracts, selectors, and extensions, Michigan Math. J. 42 (1995) 555-571.https://doi.org/10.1307/mmj/1029005313Google Scholar
  17. R. T. Rockafellar: Convex Analysis, Princeton Univ. Press, Princeton, 1970.https://doi.org/10.1515/9781400873173Google Scholar
  18. J. Saint-Pierre: Point de Steiner et sections lipschitziennes, Sém. Anal. Convexe 15(7) (1985).Google Scholar
  19. R. Schneider: On Steiner points of convex bodies, Israel J. Math. 9 (1971) 241-248.https://doi.org/10.1007/BF02771589Google Scholar
  20. G. C. Shephard: The Steiner point of a convex polytope, Canad. J. Math. 19 (1967) 1294-1300.https://doi.org/10.4153/CJM-1966-128-4Google Scholar
  21. W. Spiegel: Zur Minkowski-Additivität bestimmter Eikörperabbildungen, J. Reine Angew. Math. 286/287 (1976) 164-168.https://doi.org/10.1515/crll.1976.286-287.164Google Scholar
  22. G. Stefani, P. Zecca: Multivalued differential equations on manifolds with application to control theory, Illinois Math. J. 24 (1980) 560-575.https://doi.org/10.1215/ijm/1256047473Google Scholar
  23. E. M. Stein, G. Weiss: Introduction to Fourier Analysis on Euclidean Spaces, Princeton Univ. Press, Princeton, 1971.https://doi.org/10.1515/9781400883899Google Scholar
  24. R. A. Vitale: The Steiner point in infinite dimensions, Israel J. Math. 52 (1985) 245-250.https://doi.org/10.1007/BF02786520Google Scholar

K. Przesławski. “Lipschitz Continuous Selectors. Part I: Linear Selectors.” Journal of Convex Analysis 5 (1998), No. 2, 249–267. https://doi.org/10.68381/jca05-18