Finite Illumination of Unbounded Closed Convex Sets
نویسندگان
چکیده
If K is an unbounded closed convex subset of Ed having nonempty interior, we seek necessary and/or sufficient conditions to ensure that the boundary of K can be externally illuminated from a finite set of directions. This problem was stated as open in a recent book by Boltyanski. The tools used in this search are those developed by Visibility Theory such as the ideas of star, inner stem, visibility cell, nova and cone of recession. Mathematical Subject Classification: 52A30 52A20
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