0 v 1 3 0 M ar 1 99 5 On a subtle point of sum rules calculations : toy model
نویسندگان
چکیده
We consider a two-point correlator in massless φ 3 model within the ladder approximation . The spectral density of the correlator is known explicitly and does not contain any resonances. Meanwhile making use of the standard sum rules technique with a simple " resonance + continuum " model of the spectrum allows to predict parameters of the " resonance " very accurately in the sense that all necessary criteria of stability are perfectly satisfied.
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تاریخ انتشار 1995