# Where is all the Antimatter?

This is obviously a duplicate of If matter and antimatter... However, it's now four to five years after a swarm of videos were made on this subject. At the time, there was a consensus that the LHC would soon be able to tell us if there's some asymmetry that might explain why matter and antimatter didn't completely annihilate each other in the first few seconds of BBN.

So what is the current state of this issue? Is there any theory that can explain how a photon could split into unequal parts of matter and antimatter? How big a problem is this?

• I believe there is still no answer to your question. – João Vítor G. Lima Nov 27 '18 at 1:12
• If you want an update on some old post, the correct thing to do is to offer a bounty ("Current answers are outdated") instead of reposting it. – AccidentalFourierTransform Nov 27 '18 at 1:13
• @Joao - I've got that, but I'm wondering if the problem has grown with time. For example, we still haven't found Dark Matter, but the crisis has grown since 2015 because LUX and LHC have ruled out the more obvious SUSY models. – Quarkly Nov 27 '18 at 1:16
• @safesphere That is not correct: searches for CP violation which would explain the matter-antimatter asymmetry are an active field of research with several fronts, not just at LHC. If you have other information, please expand your comment into a proper answer. – rob Nov 27 '18 at 5:39
• @safesphere The question is why was the initial production asymmetrical. If your answer is "I don't care" that's fine, but it's a legitimate scientific query. – Señor O Nov 27 '18 at 6:55

A split big bang with two opposite time directions. Creation of matter and antimatter at the moment $$t0$$, but also at the moment $$-t0$$. Matter and antimatter are separated by the propagation of matter and antimatter in two opposite time directions.