The dream of turning solid objects invisible is an ancient one. In recent years a number of experiments have succeeded in "cloaking" (to borrow a term from Star Trek) specialized materials, rendering them transparent to some wavelengths of light. True invisibility, however, remains in the realm of science fiction. The challenge is to create conditions in which electromagnetic fields are the same on both sides of a solid object, meaning that the presence of that object is masked.
A new experiment reported in Science involves far simpler conditions and materials than any previous attempts. Researchers Fedor Gömöry et al. constructed a cylinder of nested magnetic and high-temperature superconducting materials that precisely manipulates an external uniform magnetic field until it is the same on both sides of the object. From a magnetic point of view, the cylinder is cloaked. The technique is far from being able to mask a large object at room temperature: the cloak uses a magnetic field that doesn't vary in space or time, and the superconductor requires that the entire system be cooled to 77 degrees above absolute zero. Nevertheless, the entire setup is a significant advance and requires much simpler conditions than prior cloaking experiments.
Read the comments on this post
