Because light, moves over 3 axis through 6D space in reality, not as seen on a 2D X-Y (photo) frame (of 2D math reference), not just between point A and point B, like (laser) photons in a lab.(energy is 3D, Mass is 3D, motion in space is 3D, Light is projected through 3D, and is then seen as 2D only, and the math is 2D as well.) e=mc2 results in a xy axis mathematical point, on paper, sort of working, for xY motion, on paper. what has e=mc2 given us, really?
Welcome to the 21st century.
