Abstract
In this paper, generalizing the notion of a path we define ak-area to be the setD={g(t):t ∈J} on thek-skeleton of a convex compact setK in a Hilbert space, whereg is a continuous injection map from thek-dimensional convex compact setJ to thek-skeleton ofK. We also define anE k-area onK, whereE k is ak-dimensional subspace, to be ak-area with the propertyπ(g(t))=t,t ∈π(K), whereπ is the orthogonal projection onE k. This definition generalizes the notion of an increasing path on the 1-skeleton ofK. The existence of such sets is studied whenK is a subset of a Euclidean space or of a Hilbert space. Finally some conjectures are quoted for the number of such sets in some special cases.
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Leoni Dalla,Increasing paths on the one-skeleton of a convex compact set in a normed space, Pacific J. Math.124 (1986), 289–294.
Leoni Dalla,Increasing paths leading to a face of a convex compact set in a Hilbert space, Acta Math. Hung.52 (1988), 195–198.
G. Ewald, D. G. Larman and C. A. Rogers,The directions of line-segments and of the r-dimensional balls on the boundary of a convex body in Euclidean space, Mathematika17 (1970), 1–20.
S. Gallivan,On the number of strict increasing paths in the one-skeleton of a convex body, submitted.
S. Gallivan,On the number of disjoint increasing paths in the one-skeleton of a convex body leading to a given exposed face, Isr. J. Math.32 (1979), 282–288.
W. V. D. Hodge and D. Pedoe,Algebraic Geometry, I, Chapter 7, Cambridge University Press, 1947.
D. G. Larman,On the one-skeleton of a compact convex set in a Banach space, Proc. London Math. Soc. (3)34 (1977), 117–144.
D. G. Larman and C. A. Rogers,Increasing paths on the one-skeleton of a convex body and the directions of line segments on the boundary of a convex body, Proc. London Math. Soc. (3)23 (1971), 683–698.
V. A. Zalgaller,On the k-dimensional directions singular for a convex body in R n, Zap. Nauchn. Semin. Leningrad Otdel. Matem. Inst., Akad. Nauk SSSR27 (1972), 67–72; English translation: J. Sov. Math.3 (1975), 437–441.
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Dalla, L. On a class of some special sets on thek-skeleton of a convex compact set. Israel J. Math. 68, 353–364 (1989). https://doi.org/10.1007/BF02764990
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DOI: https://doi.org/10.1007/BF02764990