Answers are grounded in this paper and cite their sources.
I. J. Schoenberg, On Certain Metric Spaces Arising From Euclidean Spaces by a Change of Metric and Their Imbedding in Hilbert Space, Annals of Mathematics, Second Series, Vol. 38, No. 4 (Oct., 1937), pp. 787-793
No takes yet. Share an insight, caveat, or question.
I. J. Schoenberg (1937) studied this question.
Synapse has enriched 5 related papers. Consider them for comparative context: