Nobody really knows what would happen if a lump of antimatter and matter come together - tiny particles, yes, big lumps, no. It has been speculated that a fuzzy interaction zone would form, keeping the two sides apart. This is like the Leidenfrost layer that forms if a drop of water is sprinkled on a hot skillet - it dances around. At the right temperature, several hundred degrees, steam insulates the water drop and it lasts much longer than at a higher or lower temperature. Another example is walking on hot coals with bare feet. So, similar to the Angels and Demons movie, antimatter may not blow up all at once. Of course, it is possible that the rate of interaction is great enough that for all intents and purposes, it looks like a big explosion. You might have to be more than 10 miles away from the 2 guys when they are fighting, but the universe is safe.
Review of The Alternative Factor
