A difference in the properties of matter and antimatter could help explain our universe – but a property called the Lamb shift is similar in particles of both
Source:
https://www.newscientist.com/article/mg24532703-800-antimatter-looks-just-like-matter-which-is-a-big-problem-for-physics/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home