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Fabio Lepreti is a physicist who studies statistical and dynamical models of turbulence. A paper with Vincenzo Carbone and Pierluigi Veltri, published in 2006 and archived in 2007, constructed a model for the spatial and temporal unevenness of turbulent dissipation. The model combined a shell model of turbulence for transfer between scales with rules for distributing the dissipated energy across space.^[ref]

A control parameter adjusted the strength of intermittency, and numerical simulations tested the resulting scaling. This addresses a physical distinction: an average dissipation rate can be steady even when individual locations undergo rare intense bursts. A model that reproduces the average alone has not yet explained that concentration in space and time.^[ref]

Guido Boffetta is a physicist whose research includes turbulence and nonlinear dynamical systems. His University of Turin profile identifies work in turbulence research groups and projects on extreme events in turbulent convection.^[ref]

A 1999 first-authored paper with Vincenzo Carbone, Pierluigi Veltri and other collaborators tested models of solar flares using the time between successive bursts. Twenty years of observations showed a power law in those intervals, with an exponent near $2.4$. The comparison challenged the Poisson-like timing predicted by particular models and tested a shell model of turbulence against several observed distributions.^[ref]

The methodological point is that matching burst sizes is different from matching burst timing. In an ideal constant-rate Poisson process, the probability of waiting longer than $t$ is $e^{-\lambda t}$; a persistent power-law tail has a different pattern. This supplies an additional observable with which to distinguish models. It does not mean that a fitted exponent alone uniquely identifies the physical mechanism.

By Luca Sorriso-Valvo, Raffaele Marino, Vincenzo Carbone, Fabio Lepreti, Pierluigi Veltri, Alain Noullez, Roberto Bruno, Bruno Bavassano, Ermanno Pietropaolo.

Physical Review Letters 99, 115001 (2007), DOI doi.org/10.1103/PhysRevLett.99.115001 . Primary byline as listed in the archive. Abstract and mixed third-order structure functions: Ulysses velocity/magnetic observations and evidence of a magnetohydrodynamic inertial energy cascade.

Pierluigi Veltri is a physicist whose publications develop and test models of magnetohydrodynamic turbulence. With Vincenzo Carbone and colleagues, he coauthored a 1999 study comparing the waiting times between solar flares with predictions of proposed mechanisms for impulsive energy release. The study analyzed twenty years of observations and found a power law in quiescent times, rather than the Poisson-like timing predicted by the particular models being tested.^[ref]

The scientific point is that a burst-size distribution alone may leave competing explanations plausible. Measuring the time between bursts adds another test. The investigators also compared the observations with a shell model of turbulence, in which interacting bands of scales represent an energy cascade. Agreement across several distributions gives a more demanding comparison than matching one fitted exponent.^[ref]

These are collective results, rather than evidence that one author performed every part of the analysis. They illustrate Veltri's work at the interface between nonlinear models and observable statistics of space plasmas.

Vincenzo Carbone is a physicist whose work connects magnetohydrodynamic turbulence, the solar wind and nonlinear statistical models. The European Geosciences Union's official 2025 medal citation identifies contributions to models of the energy cascade, the multiscale organization of fluctuations and shell models of turbulence applied to solar phenomena.^[ref]

The modeling strategy represents interacting ranges of scale with a smaller dynamical system, making it possible to test how transfer toward smaller structures produces uneven dissipation. A useful question is whether a model matches several kinds of observations simultaneously: the distribution of event strengths, their timing and their scale dependence. His coauthored work with Pierluigi Veltri on solar flare timing supplies one such comparison.^[ref]