claim: Mikhail Prokhorov is not a former chairman.
evidence: In mathematics , the support -LRB- sometimes topological support or spectrum -RRB- of a measure μ on a measurable topological space -LRB- X , Borel -LRB- X -RRB- -RRB- is a precise notion of where in the space X the measure `` lives '' .. mathematics. mathematics. measure. Measure space. measurable. measurable space. topological space. topological space. It is defined to be the largest -LRB- closed -RRB- subset of X for which every open neighbourhood of every point of the set has positive measure .. measure. Measure space. closed. closed set. subset. subset. open. open set. neighbourhood. neighbourhood ( mathematics ). set. Set ( mathematics )