15 v 2 7 O ct 1 99 5 Four - Loop Perturbative Expansion for the Lattice N - Vector Model Sergio
نویسنده
چکیده
We compute the four-loop contributions to the β-function and the anomalous dimension of the field for the O(N)-invariant N -vector model. These results are used to compute the second analytic corrections to the correlation length and the general spin-n susceptibility.
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تاریخ انتشار 2008