Listening to In Our Time talking about antimatter, there were a whole lot of earth shattering revelations.  Such as dark matter.  If you look at how fast the galaxies are spinning, they should (knowing the weights of stars) actually be falling apart.  In fact, the stars you can see only account for about 10% of the mass which must be present for gravity to keep them in 1 place.  So where's the rest?

Similarly, antimatter gets produced all the time eg cosmic rays, positron emission scanners in hospitals.  But it gets wiped out instantly by whatever matter it runs into.  So why is there so much matter, and so little antimatter?  There must be an imbalance, an asymmetry, in survival: when they look at the early universe, where matter and antimatter would have been slugging it out for survival, they have calculated that just 1 in 10 billion particles would have to survive annihilation by antimatter to end up with the universe we have to day.

We are but flotsam in the dark and deathly business of the universe.