Antiparticle

Given the existence of the antiproton, antineutron, and antielectron, one might imagine the existence of antiatoms, atoms that are identical to the atoms of everyday life but have mirror image electrical charges and mirror image magnetic moments. In fact, some scientists believe that a whole universe of antimatter made of antiatoms may actually exist in some dimensions of which we are not aware.

Locating the existence of such an antiuniverse would be very difficult, however. When an antiparticle comes into contact with its mirror image—an antielectron with an electron, for example—the two particles annihilate each other and their mass is converted to energy. Thus, any time matter comes into contact with antimatter, both are destroyed and converted into energy.