Merrill Lynch’s former chief energy trader was sentenced Friday to 3 1/2 years in prison by a judge who said his theft of $43 million from the brokerage was the action of “an arrogant would-be master-of-the-universe.”

Daniel L. Gordon, 29, of Old Lyme, Conn., was sentenced by U.S. District Judge Gerard E. Lynch after Gordon apologized and said his guilty plea “will serve as my scarlet letter for the rest of my life.” He was also ordered to pay a $100,000 fine and to forfeit the $43 million.