Researchers from the Faculty of Physics at the University of Warsaw, the Military University of Technology (Poland), IBM Research Zurich and the French National Centre for Scientific Research (CNRS) have observed a new quantum state of matter known as a supersolid in an exciton-polariton Bose-Einstein condensate. Remarkably, the phenomenon occurs not at temperatures close to absolute zero, but at room temperature. The results have been published in Science Advances.