# Can an anti-hydrogen atom decay into a hydrogen atom?

I was thinking about Baryon asymmetry just to mess around with ideas and thought about this. Could it be that all the anti-matter decayed into matter?

• General tip: Check the right margin for duplicates. – Qmechanic Nov 5 '17 at 17:57
• Decay is involved from a higher energy state to a lower energy state, and hydrogen has exactly the same energy as antihydrogen, within the standard model of particle physics. you are talking of lepton number and baryon number violations: quarks have to become antiquarks and the electron a positron – anna v Nov 5 '17 at 18:14
• Not necessarily, I guess. Those can be conserved by the formation of other particles. – looneysnoop Nov 6 '17 at 10:35

That would also require a change of sign in total lepton number. However, theories claiming only $B-L$ need be conserved are consistent with the process that you propose. Sadly, there is still no proof of leptoquarks.