A new antitrust ruling against Alphabet could potentially lead to a breakup.Shares of Alphabet (GOOG -2.94%) (GOOGL -2.97%) were sliding today on a report from Bloomberg last night that the U.S. Department of Justice was considering a full-scale breakup of the company following earlier lawsuits, including a ruling by a judge last week that said payments to companies like Apple and Samsung to be the default search engine on their devices constituted an illegal monopoly.As of 11:35 a.m. ET on Wednesday, Alpha ...