Virtual particles “pop into existence” in matter/antimatter pairs and then “pop out” as they annihilate each other all the time. In one interpretation, an electron positron pair (for example) can be thought of as one electron that loops around and goes back in time. Due to CPS symmetry, this backward path looks like a positron. https://www.youtube.com/watch?v=9dqtW9MslFk
Virtual particles “pop into existence” in matter/antimatter pairs and then “pop out” as they annihilate each other all the time. In one interpretation, an electron positron pair (for example) can be thought of as one electron that loops around and goes back in time. Due to CPS symmetry, this backward path looks like a positron. https://www.youtube.com/watch?v=9dqtW9MslFk