Third order renormalization group applied to the attractive one – dimensional Fermi gas Paolo
نویسنده
چکیده
We consider a Callan–Symanzik and a Wilson renormalization group (RG) approach to the infrared problem for interacting fermions in one dimension with backscattering. We compute the third order (two–loop) approximation of the beta function using both methods and compare it with the well known multiplicative Gell–Mann Low approach. We point out a previously unnoticed strong instability of the third order fixed point with respect to an arbitrary dimensionless parameter, which suggests a RG flow toward a strong coupling phase.
منابع مشابه
On Third Order Renormalization Group applied to the attractive one–dimensional Fermi Gas
We consider a Callan–Symanzik and a Wilson Renormalization Group approach to the infrared problem for interacting fermions in one dimension with backscattering. We compute the third order (two–loop) approximation of the beta function using both methods and compare it with the well known multiplicative Gell–Mann Low approach. We point out an unnoticed qualitative dependence of the third order fi...
متن کاملThird order renormalization group applied to the attractive one – dimensional Fermi gas
We consider a Callan–Symanzik and a Wilson Renormalization Group approach to the infrared problem for interacting fermions in one dimension with backscattering. We compute the third order (two–loop) approximation of the beta function using both methods and compare it with the well known multiplicative Gell–Mann Low approach. We point out a previously unnoticed qualitative dependence of the thir...
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