Convexity of a small ball under quadratic map
نویسندگان
چکیده
منابع مشابه
Convexity of the Image of a Quadratic Map via the Relative Entropy Distance
Abstract. Let ψ : R −→ R be a map defined by k positive definite quadratic forms on R. We prove that the relative entropy (Kullback-Leibler) distance from the convex hull of the image of ψ to the image of ψ is bounded above by an absolute constant. More precisely, we prove that for every point a = (a1, . . . , ak) in the convex hull of the image of ψ such that a1 + . . . + ak = 1 there is a poi...
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ژورنال
عنوان ژورنال: Linear Algebra and its Applications
سال: 2016
ISSN: 0024-3795
DOI: 10.1016/j.laa.2015.09.005