Superconductivity2026-07-092 minarXiv:2607.08353When the Quantum Choir Falls Silent: Sound as a Detector of SuperfluiditySuperfluidity, a state in which matter flows without friction, has long remained elusive in neutral Bose condensates of excitons.Giovanni Midei·Filippo Pascucci·Milorad V. Milosevìc·Jacques Tempere·David Neilson·Andrea Peraliquantum Hall effectJosephson effectKlaus von KlitzingsuperconductivitysuperfluidityBose-Einstein condensate👍👎☆SimplePopularAdvanced