An amplifier devised to boost light, sound or other waves while hiding them inside an invisible container could lead to the construction of a quantum microscope that captures quantum waves and monitors electronic processes on computer chips. The University of Washington system, dubbed “Schrödinger’s hat,” refers to the quantum mechanical paradox of Schrödinger’s cat and the creation of something from what appears to be nothing. This graphic shows a matter wave hitting a so-called Schrödinger’s hat. The wave inside the container is magnified. Outside, the waves wrap as though they had never encountered any obstacle. Courtesy of G. Uhlmann, University of Washington. “In some sense, you are doing something magical, because it looks like a particle is being created,” said Gunther Uhlmann, a mathematics professor at the university. “It’s like pulling something out of your hat.” Matter waves also can be shrunk inside the system, although concealing very small objects is not so interesting, Uhlmann said. “You can isolate and magnify what you want to see and make the rest invisible,” he said. By manipulating waves, the mathematicians hope to create a quantum microscope that can capture quantum waves. “You can amplify the waves tremendously,” Uhlmann said. “And although the wave has been magnified a lot, you cannot see what is happening inside the container.” Previously, the team collaborated on the math that formulates invisibility cloaks. The international group also created wormholes in which waves disappear in one place and reappear in another. The new system has the potential to make various types of waves disappear, including longer ones such as quantum matter waves, sound and microwaves. “From the experimental point of view, I think the most exciting thing is how easy it seems to be to build materials for acoustic cloaking,” Uhlmann said. “We hope that it’s feasible, but in science you don’t know until you do it.” The team is now working toward building a prototype. The findings appeared in the Proceedings of the National Academy of Sciences (doi: 10.1073/pnas.1116864109).