n an antimatter warp drive engine, an electron traveling at a speed of 0.410c meets an antielectron (i.e., a positron) head on, traveling at a speed of 0.740c. They annihilate each other, and produce two gamma rays. What is the total energy of the resulting gamma rays? The electron and the positron have identical mass, of 9.11×10−31 kg, or 0.511 MeV/c2.