Scientists have demonstrated that negative refraction can be achieved using atomic arrays -- without the need for artificially manufactured metamaterials. Scientists have long sought to control light ...

For the first time, scientists have demonstrated that negative refraction can be achieved using atomic arrays - without the need for artificially manufactured metamaterials. Scientists have long ...

Well, OK, not exactly. A beam of light could pass through air all day long (as long as you have a layer of air 26 billion kilometers long) and not deviate a whit. But if the density of that air ...