Comment Re:Matter, anti-matter... (Score 2) 393
Are we sure there were equal amounts?
The way I have understood what's been said so far is this. The universe started with equal amounts matter and antimatter. Matter and anti-matter can only be produced and annihilated in equal amounts. Today we have reached a state, where there is much more matter than antimatter.
This is obviously inconsistent. So one of those three statements has to be wrong. I for one don't know which one of them is wrong. And I also haven't come across a physicist who had solid evidence for which of them is wrong.
One possibility I have been wondering about is that of antimatter galaxies. Seen from a distance, wouldn't an antimatter galaxy look exactly like one made of matter? I have been told this is not a possibility either, since that would imply that somewhere there would have to be a boundary between matter and antimatter, where a lot of annihilation would be going on and producing gamma-radiation, which we have not observed. I am wondering if the reason we are not observing this boundary is because those regions of space are by now so empty that there is no significant amount of annihilation going on anymore. Or could it possibly be the case that those boundaries are actually so far apart, that there just isn't any such boundary within our event-horizon. That would imply that the antimatter is out there somewhere beyond the event horizon and maybe 10^12 years from now it will be visible.