Needed: a new definition of diffusion

The conventional definition of diffusion of sound in resonating systems has important major deficiencies. It is oriented toward acoustical spaces and is difficult to apply to the vibrations of structural systems. Second, it is impossible to reach the state of perfect diffusion in any finite space, and any reasonable metric of diffusion predicts finite system diffusion as very far from the ideal. Third, the definition applies only to systems of irregular geometry. A new definition of diffusion is proposed that would provide a continuous metric for finite systems, acoustical or otherwise, and approaches the current definition for very large irregular systems.