Chaos and Ergodicity across the Energy Spectrum of Interacting Bosons

We identify the chaotic phase of Bose-Hubbard Hamiltonian by energy-resolved correlation between spectral features and structural changes associated eigenstates as exposed their generalized fractal dimensions. The eigenvectors are shown to become ergodic in thermodynamic limit, configuration space Fock basis, which random matrix theory offers a remarkable description typical structure. distributions dimensions, however, ever more distinguishable from Hilbert dimension grows.