Given the discussion from:
it appears that a 1974 paper by Morgan gives the criteria for when a distance metric can be embedded in Euclidean space. My first question is, what are some examples of metrics that satisfy his criteria? Some popular metrics that immediately come to mind are:
Levenstein distance (https://en.wikipedia.org/wiki/Levenshtein_distance)
Jaccard distance (https://en.wikipedia.org/wiki/Jaccard_index)
Can they be represented in R^n?
My second question is, if a metric does meet the criteria, how do we place the points in Euclidean space?
Thirdly, Morgan's result seems really profound. Why is it hardly cited? Is there an equivalent set of criteria that is more widely known?