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  • 1 Budapest University of Technology, Müegyetem rakpart 1-3., Budapest 1111, Hungary
  • 2 Budapest University of Technology and Economics, Budapest, Egry József u. 1., 1111, Hungary
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In 1944, Santaló asked about the average number of normals through a point of a given convex body. Since then, numerous results appeared in the literature about this problem. The aim of this paper is to add to this list some new, recent developments. We point out connections of the problem to static equilibria of rigid bodies as well as to geometric partial differential equations of surface evolution.

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