NurPhoto/Getty Images "If you don't think there are opportunities with AI, then in my mind you are a complete moron." That comes from the head of Norway's sovereign wealth fund, which is the world's biggest stock investor. The fund made $143 billion in the first half of the year, helped by top US tech stocks. Norway's sovereign wealth fund is bullish on artificial intelligence, with the nascent technology contributing to the portfolio's big gains this year. The $1.4 trillion fund, which is also the world's single biggest stock market investor, has returned 10% year to date, amounting to about $143…