This is today’s edition of The Download, our weekday newsletter that provides a daily dose of what’s going on in the world of technology. Digital twins of human organs are here. They’re set to transform medical treatment. Steven Niederer, a biomedical engineer at the Alan Turing Institute and Imperial College London, has a cardboard box filled with 3D-printed hearts. Each of them is modeled on the real heart of a person with heart failure, but Niederer is more interested in creating detailed replicas of people’s hearts using computers. These “digital twins” are the…