We give two characterizations of cones over ellipsoids. Let CC be a closed convex linear cone in a finite-dimensional real vector space. We show that CC is a cone over an ellipsoid if and only if the affine span of ∂C∩∂(a−C)\partial C \cap \partial(a - C) has dimension dim⁡(C)−1\dim(C) - 1 for every point aa in the relative interior of CC. We also show that CC is a cone over an ellipsoid if and only if every bounded section of CC by an affine hyperplane is centrally symmetric.

Contact details are reproduced from the original publication and may be historical.

Jesús Jerónimo-Castro

Facultad de Ingenieria, Universidad Autónoma de Querétaro, Cerro de las Campanas s/n, C.P. 76010, Querétaro, México

Tyrrell B. McAllister

Dept. of Mathematics, University of Wyoming, Laramie, WY 82071, U.S.A.

tmcallis@uwyo.edu
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J. Jerónimo-Castro, T. B. McAllister. “Two Characterizations of Ellipsoidal Cones.” Journal of Convex Analysis 20 (2013), No. 4, 1181–1187. https://doi.org/10.68381/jca20063