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تسجيل مستخدم جديدImpurity Greens function of a one-dimensional Fermi-gas
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We consider a one-dimensional gas of spin-1/2 fermions interacting through $delta$-function repulsive potential of an arbitrary strength. For the case of all fermions but one having spin up, we calculate time-dependent two-point correlation function of the spin-down fermion. This impurity Greens function is represented in the thermodynamic limit as an integral of Fredholm determinants of integrable linear integral operators.
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