Physicist: Anti-matter is exactly the same as ordinary matter but opposite, in very much the same way that a left hand is exactly the same as a right hand… but opposite. Anti-matter acts, in (nearly) every way we can determine, exactly like matter. Like the sign of electrical charge or the handedness of hands, the nature of matter and anti-matter are indistinguishable until you compare them. Conveniently, anti-protons have the opposite charge and are pushed in the opposite direction by magnets. The highest energy particle interactions we can witness happen in the upper atmosphere; to see them we just have to be patient.