  Spectral statistics of disordered systems encode Thouless and Heisenberg time
scales whose ratio determines whether the system is chaotic or localized.
Identifying similarities between system size and disorder strength scaling of
Thouless time for disordered quantum many-body systems with results for 3D and
5D Anderson models, we argue that the two-parameter scaling breaks down in the
vicinity of the transition to the localized phase signalling subdiffusive
dynamics.
