Cone condition

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Template:Short description In mathematics, the cone condition is a property which may be satisfied by a subset of a Euclidean space. Informally, it requires that for each point in the subset a cone with vertex in that point must be contained in the subset itself, and so the subset is "non-flat".

Formal definitions

An open subset S of a Euclidean space E is said to satisfy the weak cone condition if, for all 𝒙S, the cone 𝒙+V𝒆(𝒙),h is contained in S. Here V𝒆(𝒙),h represents a cone with vertex in the origin, constant opening, axis given by the vector 𝒆(𝒙), and height h0.

S satisfies the strong cone condition if there exists an open cover {Sk} of S such that for each 𝒙SSk there exists a cone such that 𝒙+V𝒆(𝒙),hS.

References