Self-similar temporal behavior of gamma-ray bursts

We apply Fourier analysis to 214 light curves of long gamma-ray bursts and study the statistical properties of their power density spectra (PDSs). The averaged PDS is found to follow a power law of index -5/3 over almost two decades of frequency, with a break at similar to 2 Hz. Individual PDSs are exponentially distributed around the power law. It provides evidence that t he diversity of the bursts is due to random realizations of the same proces s that is self-similar over the full range of timescales. The -5/3 slope of the average spectrum may indicate that gamma-ray bursts are related to a p henomenon well studied in hydrodynamics-fully developed turbulence.