What happened before the big bang? According to Stephen hawking

Stephen hawking, one of the famous physicists has an answer on what happened before the big bang? We know the big bang expansion has begun 13.8 billion years ago. All matter in the universe emitted from a peculiarity to create the cosmos. https://spinonews.com/2018/03/06/what-happened-before-the-big-bang-according-to-stephen-hawking/