I'm new here so humour me if this has already been discussed. Could someone please explain some possibilities for our present matter/antimatter situation? i.e. why we have so much of one and so little of the other? Also, could someone please present some evidence for why there isn't (or can't be) large quantities of antimatter elsewhere in the universe? I couldn't find anything to disprove the notion that though there aren't large amounts of antimatter in our local vicinity (hence a lack of detected largescale annihilation), elsewhere in the universe antimatter could be abundant. Unexplained gamma rays--could those be antimatter sources? I haven't researched this as much as I probably should but I figured this was as good a source for conjectures as any. =) Thank you.