Bridgewater State University authorities said yesterday they are investigating a student’s account that she was punched in the face Thursday night on campus by a woman who objected to her editorial in the school newspaper supporting same-sex marriage. In an interview, the alleged victim said that while she is openly gay, she does not believe her alleged assailant was aware of her sexual orientation. A college administrator said the school regarded the attack as a display of intolerance directed at a fellow student’s political views.