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Scale Invariance and Lack of Self-Averaging in Fragmentation

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 نشر من قبل Eli Ben-Naim
 تاريخ النشر 1999
  مجال البحث فيزياء
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We derive exact statistical properties of a class of recursive fragmentation processes. We show that introducing a fragmentation probability 0<p<1 leads to a purely algebraic size distribution in one dimension, P(x) ~ x^{-2p}. In d dimensions, the volume distribution diverges algebraically in the small fragment limit, P(V)sim V^{-gamma} with gamma=2p^{1/d}. Hence, the entire range of exponents allowed by mass conservation is realized. We demonstrate that this fragmentation process is non-self-averaging. Specifically, the moments Y_alpha=sum_i x_i^{alpha} exhibit significant fluctuations even in the thermodynamic limit.



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