But the world will notice. And what a sad day it would be for the universe! On the other hand, if another me was somehow created at the same time, with the same memories and the same brain patterns, no one will notice any difference. Not me. Nor anybody. So, for all reasons and purposes, there will be no difference. That makes no sense. If they are identical, then they are identical, which means there is no way to distinguish between the two. If you disassemble a house, brick by brick, move it in another place, and they reassemble it without any loss of information, then it's the same house. Beside, if you look small enough, matter is basically empty space, energy, and information. If we can transport energy and information, then we can transport matter. In the end, it all boils down if you believe there is some "ineffable" quality in matter that can't be measured, copied, or transported (even using "magical" technology as the transporter). Basically, if you believe in souls.