Dynamic Fluctuations in a Short-range Spin Glass Model
نویسنده
چکیده
We study the dynamic fluctuations of the soft-spin version of the Edwards-Anderson model in the critical region for T → T+ c . First we solve the infinite-range limit of the model using the random matrix method. We define the static and dynamic 2-point and 4-point correlation functions at the order O(1/N) and we verify that the static limit obtained from the dynamic expressions is correct. In a second part we use the functional integral formalism to define an effective short-range Lagrangian L for the fields δQ i (t1, t2) up to the cubic order in the series expansion around the dynamic Mean-Field value Q(t1, t2). We find the more general expression for the time depending non-local fluctuations, the propagators [〈δQ i (t1, t2)δQ αβ j (t3, t4)〉ξ ]J , in the quadratic approximation. Finally we compare the long-range limit of the correlations, derived in this formalism, with the correlations of the infiniterange model studied with the previous approach (random matrices).
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تاریخ انتشار 2008