Physicists track how continuous changes in dimensionality affect collective properties of a superfluid

An international research team from Innsbruck and Geneva has, for the first time, probed the dimensional crossover for ultracold quantum matter. In the regime between one and two dimensions, the quantum particles perceive their world as being 1D or 2D depending on the length scale on which they are probed: For short distances, their world is 1D, but it is 2D for long distances.