A new theory says there might be an “anti-universe” that has been running backward in time since before the Big Bang.
The theory suggests that since the early universe was small, hot, and dense, it was uniform enough that time looked symmetric, going backward and forwards. This is based on the law of CPT symmetry, which says that charge, parity, and time, are symmetrical, and you will see the same reaction if they are flipped.
If this belief were true, it would suggest that dark matter is simply a new type of neutrino or a tiny, nearly massless particle and that there was no period of exponential expansion during the very early universe. Future experiments investigating gravitational waves or neutrinos could help to uncover the existence of this mirror anti-universe.
Does this sound like a Marvel movie to you? Let us know what you think.