this post was submitted on 27 Sep 2023
434 points (98.9% liked)
Science
13206 readers
4 users here now
Subscribe to see new publications and popular science coverage of current research on your homepage
founded 5 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
I've heard hypothecies that antimatter was normal matter going back in time. But this disproves it since it would have been going in reverse in gravity.
I don’t think it works like that, it’s not as simple as doing the opposite of what we would normally expect the flow of time to dictate.
Nope it doesn't. But if it did it would have been neat!
Unless antimatter is also antigravity and the two cancel each other out, making it look normal to us.
In many instances it is very convenient to think of antimatter as normal matter going back in time. This is what makes Feynman diagrams so easy to use and powerful.
Furthermore, CPT symmetry is a necessary condition for basically all scientific theories. This means that reversing time is literally identical to reversing 'charge' and 'parity' together - and in this context, reversing charge means swapping all matter for anti-matter and visa-versa. Reversing 'parity' roughly means swapping left and right across the whole universe.
... Anyway, CPT doesn't directly tell us that anti-matter particles are normal matter going back in time, but it does imply that that isn't a bad way of thinking about it.