John McAfee challenges Jamie Dimon's bitcoin skepticism McAfee challenged Dimon's assertion that bitcoin is a "fraud" that will eventually blow up. Miners invest "massive" amounts of supercomputing power and electricity in creating bitcoins, McAfee on CNBC's "Fast Money." John McAfee on Wednesday challenged JPMorgan CEO Jamie Dimon's skepticism of bitcoin. Dimon on Tuesday called bitcoin a "fraud" that will eventually blow up. McAfee, whose company MGT Capital Investments mines the cryptocurrency, said he respects Dimon and people in his position…