Quantum liquids defy bosons and fermions, revealing new exclusion statistics.
Particles interacting in a special way can act neither like bosons nor fermions, but have their own rules called fractional exclusion statistics. This happens when particles interact over long distances in a quantum liquid. The particles form enlarged pseudo-Fermi surfaces, leading to different behaviors for bosons and fermions. This shows that the way particles interact with each other determines their exclusion statistics.