  The process of magnetic reconnection when studied in Nature or when modeled
in 3D simulations differs in one key way from the standard 2D paradigmatic
cartoon: it is accompanied by much fluctuations in the electromagnetic fields
and plasma properties. We developed a new diagnostics, the topographical
fluctuations analysis (TFA) to study the spectrum of fluctuations in the
various regions around a reconnection site. We find that fluctuations belong to
two very different regimes. The first regime is better known, it develops in
the reconnection outflows and is characterized by a strong link between plasma
and electromagnetic fluctuations leading to momentum and energy exchanges via
anomalous viscosity and resistivity. But there is a second, new, regime: it
develops in the inflow and in the region around the separatrix surfaces,
including the reconnection diffusion region itself. In this new regime the
plasma remains laminar but the electromagnetic fields fluctuates strongly. We
present an analogy with the smooth continuous motion of the bow of a violin
producing the vibrations of the strings to emit music.
