Progress of Theoretical Physics

Higher-Order Calculations for Weakly Random System in 1/n Expansion

K. Ideura, Yutaka Okabe, R. Abe

Published Apr 1, 1981• 0 citations

Abstract

In the scheme of 1/n expansion the effects of weak randomness on critical exponents are investigated. By extending the lowest-order argument of Abe, the higher-order terms of the O(a3) and of the O(1/n) are studied(a being a measure of the randomness). Though each diagram constituting higher-order terms shows the logarithmic dependence, which has the possibility of modifying critical exponents, they are canceled out when summed up. It is concluded that random impurities are irrelevant to critical exponents.

DOI: 10.1143/ptp.65.1179

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