Exactly solvable sandpile with fractal avalanching
A simple one-dimensional sandpile model is constructed which possesses exact analytical solvability while displaying both scale-free behavior and fractal properties. The sandpile grows by avalanching on all scales, yet its shape and energy content are described by a simple, continuous (but nowhere differentiable) analytical formula. The avalanche energy distribution and the avalanche time series are both pou er lows with index -1 (''1/f spectra''). [S1063-651X(99)00306-2].