# Convex sets, metric space of

From Encyclopedia of Mathematics

The family of compact convex sets (cf. Convex set) $F$ in a Euclidean space $E^n$ endowed with the Hausdorff metric: $$ \rho(F_1,F_2) = \sup_{x\in F_1,\,y\in F_2} \{\rho(x,F_2), \rho(y,F_1) \} $$ This space is boundedly compact (cf. Blaschke selection theorem). For analogues of metric spaces of convex sets (other metrizations, non-compact sets, classes of sets, other initial spaces) see [1].

#### References

[1] | B. Grünbaum, "Measures of symmetry for convex sets" , Proc. Symp. Pure Math. , 7 (Convexity) , Amer. Math. Soc. (1963) pp. 233–270 |

#### Comments

Metric spaces of convex sets (in particular the metrization by the symmetric difference metric) play a basic role in the foundations of analysis in convex geometry. New important results in convex geometry are given in [a1], [a3]; [a2] gives a general and axiomatic approach.

#### References

[a1] | P.M. Gruber, "Approximation of convex bodies" P.M. Gruber (ed.) J.M. Wills (ed.) , Convexity and its applications , Birkhäuser (1983) pp. 131–162 |

[a2] | H. Hadwiger, "Vorlesungen über Inhalt, Oberfläche und Isoperimetrie" , Springer (1957) |

[a3] | R. Schneider, "Valuations on convex bodies" P.M. Gruber (ed.) J.M. Wills (ed.) , Convexity and its applications , Birkhäuser (1983) pp. 170–247 |

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Convex sets, metric space of.

*Encyclopedia of Mathematics.*URL: http://www.encyclopediaofmath.org/index.php?title=Convex_sets,_metric_space_of&oldid=33714

This article was adapted from an original article by V.A. Zalgaller (originator), which appeared in Encyclopedia of Mathematics - ISBN 1402006098. See original article