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Scaling forms for Relaxation Times of the Fiber Bundle model

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 نشر من قبل Subhrangshu Manna
 تاريخ النشر 2013
  مجال البحث فيزياء
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Using extensive numerical analysis of the Fiber Bundle Model with Equal Load Sharing dynamics we studied the finite-size scaling forms of the relaxation times against the deviations of applied load per fiber from the critical point. Our most crucial result is we have not found any $ln (N)$ dependence of the average relaxation time $langle T(sigma,N) rangle$ in the precritical state. The other results are: (i) The critical load $sigma_c(N)$ for the bundle of size $N$ approaches its asymptotic value $sigma_c(infty)$ as $sigma_c(N) = sigma_c(infty) + AN^{-1/ u}$. (ii) Right at the critical point the average relaxation time $langle T(sigma_c(N),N) rangle$ scales with the bundle size $N$ as: $langle T(sigma_c(N),N) rangle sim N^{eta}$ and this behavior remains valid within a small window of size $|Delta sigma| sim N^{-zeta}$ around the critical point. (iii) When $1/N < |Delta sigma| < 100N^{-zeta}$ the finite-size scaling takes the form: $langle T(sigma,N) rangle / N^{eta} sim {cal G}[{sigma_c(N)-sigma}N^{zeta}]$ so that in the limit of $N to infty$ one has $langle T(sigma) rangle sim (sigma - sigma_c)^{-tau}$. The high precision of our numerical estimates led us to verify that $ u = 3/2$, conjecture that $eta = 1/3$, $zeta = 2/3$ and therefore $tau = 1/2$.



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