Not 1, not 2, not 3, but 4 clones!

Xi-Jun Ren and Yang Xiang from Henan Universities in China, in collaboration with Heng Fan at the Institute of Physics of the Chinese Academy of Sciences, have produced a theory for a quantum cloning machine able to produce several copies of the state of a particle at atomic or sub-atomic scale, or quantum state, in an article about to be published in EPJ D